SCIENTIFIC ABSTRACT MASHKEVICH, V.S. - MASHKEYEV, A.K.

Document Type: 
Document Number (FOIA) /ESDN (CREST): 
CIA-RDP86-00513R001032710020-5
Release Decision: 
RIF
Original Classification: 
S
Document Page Count: 
100
Document Creation Date: 
November 2, 2016
Document Release Date: 
July 12, 2001
Sequence Number: 
20
Case Number: 
Publication Date: 
December 31, 1967
Content Type: 
SCIENTIFIC ABSTRACT
File: 
AttachmentSize
PDF icon CIA-RDP86-00513R001032710020-5.pdf9.32 MB
Body: 
24(2)t 24(7) AUTHOR: .1kiashkevich, V. S. SOV/48-22-11-6/33 ----------------- TITLE: The Method of Quasi-ITormal Coordinates in the Optics of Crystals (Metod kvazinormalInykh koordinat v optike kristallov) PERIODICAL: Izvestiya Akademii nauk SSSR. 1)erlya fizichesk~xya, 1958, Vol 22, Nr 11, pp 1308 - 1311(USSR) ABSTRACT: The present paper deals with the general principles of the method of quasi-nofmal coordinates and its application to ion crystals with a space lattice of the N&C1 type. At present, 2 approximations are beinL!- ifed in the theory of crystal lattice vibration: approxii:, tion of point atoms (ions) (Ref 4), and of dipoles (Refs In the point approximation the state of the crysta-1- particles is described by means of their shifting ut number of the elementary cell, s - number of tne p.---ticle contained therein). In the more accura'-e dipole- ap~jroxi-nation the dipole-moments are considered in Card 1/4 addition to the above mentioned va-riables. Tnese dipole- The Method of Quasi-Normal Coordinc,tes in the Optics SOV/48-22-1,--V53 of Crystals moments are caused by the defor-ation of the electron shell. This method is based on the idea of selecting the coefficients c.A in slich a way that the coordinates q12 thus obtained de:cribe both the light waves and t:.e vibrations of other than of luminous character. In this case H1, which already furnishes the relation of individual Q-vibrations in hermonic approxi-ation, will describe the single-phonon light absorption in qualitative harmony with the results of t;-;e forced oscillations m,Ahod. A concrete selection of co naturally depends on the type of crystal. It can, however, also be done in accordance with some general requirements resulting from the observation of the inner electric field. In the case of an ion crystal, when taking into account of the polarization of the particles results only in quantitative corrrctions, but does not influence the qualitative char--cter of t."-.e spectrum (Rei's 3,5). The vibration spectrum conni~-.ts of 8 brar-ches: 3 acoustic, 1 longitudinal, and 4 transverse optical branch~-s. Of Card 2/4 these the transverse optical branches are important in The Method of quasi-Normal Coordinates in the Optics SOV148-22-1-6/33 of Crystals connection with the spreading of light. In the case of an ion crystal, HI differs from zero alre~.dy in the zero-th approximation of k. In tre above nentia-.ed approximation, frequencies relating to 2 dif:'erent polarizations are in agreement. Accordingly, all results agree. Zero solutions are not to be taken into account. They result in normal initial vibrations so that: a11D C21 0. (22) 2 '(n2 1) n2 (n2 n, 2 2 1 (22) and (6McPa (k)12 = 1, determine c 11 and c 219 so that, in principle, the introduction of quasi-n3r-::ia1 coordinates is completed. There are 5 references, 4 of which are Soviet. ASSOCIATION: Kiyevskiy politekhnicheskiy institut (Kiyev Polytechnical Card 3/4 Institute) AUTHOR- Mashkevich,__V. S. SOV120-121-2-14153 TITLt: The Normal Coordinates of a Crystal LatticeWith Allowerree MW Interaction Lag (Normallnyye koordinaty k-istallicheskoy reshetki pri uchete zapazdyv&niya vzaimodeystviya) PERIODICAL: Doklady Akademii nauk SSSR, 1958, Vol. 121, Nr 2. pp. 247 - 249 (USSR) ABSTRACT: For the theoretical Investigation of a number of properties of crystals it becomes necessary to introduce normal coordinates. An elementary solution of this problem can be found for purely mechanical oscillations without consideration of the inter- action lag. In the following the author demonstrates the introduction of normal coordinates in the general case for a crystal lattice in dipole approximation. Starting from the equation of motion (disregarding the inertia of the dipole moments) and the expressions for __1' V1 U, and p the author sets up the amplitude equ,tion ( for Card 1/3 plane monochromatic waves); furthermore the equations for The Normal Coordinates of a Crystal Lattice With AUm- SOV/2o-121-2-14/53 &me for Interaction Lag --r --V -0 UCI as well as for 6 (r, t and j are given as 8 a OAF functions of q k,t). The expression I - - +1j 2 1 qa(-+ ;a(l) is obtained for ;~ E 4" (k) ia (k) OL (k ~k) the energy of the lattice. The equation of motion Is 0 a (-kj + 6j 2-'P a ( 1k -~r " ; --3P 4 q a (k)q - 0 with p"(k) q"(k) and p'(lk 4L(kj- Expressions for Land H Ftre also given. e denotation is -.0 1? the usual one ; u -atom.displacement, the dipole moment caused by the deformation of the electron shell; the index I serves for numbering the unit cells, and 9 for the atoms or ions, respectively; electric field intensity in the lattice point with the coordinates The asterisk denotes the cc n ugated complex quantities which are obtained by rFl cin *3 -1). Thus for example there holds a g k by (- Card 2/3 QCL ja (-kj.There are 3 references, 1 of which is Soviet. I The Normal Coordinates of a Crystal Lattice With SOV/2o-121-2-14/53 AUoume for Interaction Lag ASSOCIATION: Kiyevskiy politekhnicheakiy institut (Kiyev Polytechnical Institute) PRESENTED: April,8, 1958, by N.N.Bogolyubov, Member, Academy of Sciences, USSR SUBMITTED: April 7, 1958 Card 3/3 24(2) MHORs Ma&hkevich- V- 5- SOV/ 5 -6- 36-1, - 16162 TITLE# The Electrical, Optical, and Elastic Properties of the Crystals of the Type of a Diamond (Elaktricheakiye, opticheskiye i uprugiye evoystva kristallov tipa almaza) III. Di.spersion and Absorption of Light (Ill. Dispersiya i pogloshcheniye eveta) PERIODICkLi Zhurnal eksperimentallnoy i teoreticheskoy fiziki, 1959, Vol 36, Nr 1, pp 108-115 (USSR) ALBSTRACT s The author develops a quant.Ltative theory for the lattice vibrations of a homeopolar cryetal. Four parts of the present paper deal with dispersion and double refraction far from the singular point, with the quasinormal coordinates, with dispersion and double refraction in the neighborhood of the singular point, and with the absorption of light. In the fifth part, the parameters of the theory and the numerical results are given. The following conclusions can be drawn fron the considerations discussed in the present papers 1) The theory oonfirms the presence of dispersion and double refraction, which are caused by the vibrations of the atoms Card 1/2 in the crystal. Both effects have their maximum intensity The Electrical, Optical, and Elastic Properties of SOVI/56-36--l-16/62 the Crystals of the Type of a Diamond. III. Dispersion and Absorption of Light in the neighbourhood of the extreme frequency of the optical vibrations where the difference of the refraction indices for the 2 polarizations amounts to 10-4. 2) A crystal of the diamond type has 7 axes, and the directions of the optic axes coincide with the directions of the edges and diagonals of the lattice cube. The theory asserts a one-phonon absorption of light with the extreme frequency of the optic vibrations and further gives the dependence absorption on the propagation direction and on the polariza' of light. 4) An experimental verification of these results of the theory would be very advantageous, for it would permi, comparison with experimental results of that part of the theory which concerns the optical properties. There are 1 table and 8 references, 6 of which are Soviet. ASSOCIATIM Kiyevskiy politekhnicheskiy institut (Kiye-, Polytechnic Institutel SUBMITTEDs May 16, 1958 C ard 2/2 24(2) SOV/56-36-6-17/66 AUTHORs Mashkevich, V. S. TITLEo Electrical, Optical, and Elastic Properties of Crystals of the Diamond Type (Flektricheskiye, opticheskiye J uprugiye avoystva kristallov tip& almaza). IV. Interaction Between the Conductivity Electron and Lattice Vibrations (IV. Vzai- modeystviye elektrona provodimosti a kolebaniyami reshetki) PERIODICALs Zhurnal eksperimentallnoy i teoreticheskoy fiziki, 1959, Vol 36, Nr 6, PP 1736 - 1742 (USSR) kBSTRkCTs The interaction between an electron and the lattice vibrations of an ion crystal may be dealt with already in point ion approximation if the polarization connected with the vibra- tions is taken into account. In the case of a homeopolar crystal no polarization occurs in this approximation. This makes it possible to operate either with Bloch- or with de- formation potentials. The author of the prosent.piLper, by taking the atoaic dipole moments iato account, develops a quantitative theory of interaction between electron and lattice vibrations, and, by using this theory, investigates Card 1/3 the problem of the existence of polarons in homeopolar crystals Electrical, Optical, and Elastic Properties of Crystals BOV/56-36-6-17/66 of the Diamond Type. IV. Interaction Between the Conductivity Electron and Lattice Vibrations and calculates the mobility of the conductivity electron. For the purpose of simplifying calculations, the complexitv of iscenergetic surfaces in the conductivity zone is not taken into account and the simplest model of spherically symmetric surfaces with the center at pointt - 0 is used. With respect to the problem of the existence of large radius polarons the author arrives at the same conclusion as Deygen and Pekar, namely that the zonal state of the electron is stable (or metastable) and that polarons with a large radius do not exist. The interaction between electron and lattice vibrations is investigated by means of the perturbation theory. The results concerning electron mobility and its temperature dependence are compared with theexperimental results obtained by other authors, viz. for diamonds (Table 1) and germanium (Table 2). Table 3 shows the experimentally determined electron mobility at 3000K and the effective masses for diaaonds, si- licon, and germanium calculated herefrom by means of the equation (22) of this paper. A comparison with the experiments Card 2/3 shows that the-theory leads to satisfactory results. The Electrical, Optical# and Elastic Properties of Crystals BOV/56-56-6-17/66 6f the Diamond Type. IT. Interaction Between the Conductivity Electron and Lattice Vibrations author finally thanks K. B. Tolpygo for discussing the results obtained. There are 3 tables and 16 references, 7 of which are Soviet. ASSOCUTION3 Kiyevskiy politekhnicheakiy institut (Kiyev Polytechnic Insti- tute) SUBMITTEDs December 4, 1958 Card 3/3 S/139/60/000/004/026/033 3032/E5A AUTHOR: Mashkevich, V.S. --==wpm - -- ------------ TITLE: Higher Approximations in Equations Describing the State of Matter in Blectrodynamics 1~ PERIODICAL: Izvestiya rysshikh uchobnykh zavedeniy, Fizika, 1960, No.4, pp. 217-221 TEXT: The electrical and magnetic state of matter in usually described by the polarization and magnetization vectors P and 1, assuming that the relation between these vectors and the displacement and magnetic induction is: D 9 + 41fP (1) 8 H + 4V 1 (2) The equations describing the electromagnetic state of matter are then established by deducing the polarization and magnetization as a function of the fields E and H. When the wavelength of the electromagnetic wave X is large compared with molecular dimensions d, the fields can be expanded in powers of d/k. In Card 1/2 alsher Appro oe t 0 x1ft r dy4 4tio ejr,M,ft ca'ses 441 CS 4* in equations 'De S113 9/6 ord* P-1 0 the r 0 in aer Z032/a 0/ 000 Of t9rma C4.1c 0- 514 428 C' Oust ions Opp /004/026/03 C ubt u.1 a t order scribing the state of' 0 (7w 1 Cry -0 1 3 0 be Cone jr Concern pye Ital n Joe ti 0 a cluded erned On der ed and iva quire i V*d Irl th ('90, vit In quant. ror th shkev., a th n h ive t 4tio es e int f 'Rot, opt. 8urr. so lri e a. tile 4 0 hl Ch I I ) Acal acl ent. t Th ac Cher Re'r rodt, , act. 0 t rose -0 .2) C ti 'rhi I A %r - Por re--6-rej,coreat OPIC 2-der on Of 0 at ASSOC optl~ ftent VOC t 4ppr rho see Cal rat- I a en or's G-Vj Pres Ond e 131 a t 1., 0 1 144 ti en t -0 0 tr(,p friy e1 n t e1'.48 00 8 . a er er t skj Y Cj Of PO is erfts y assical. U.14 Yet' P0 poli t fticros e are Ytech eichni rher, CO ic toy '20, ni C al ell 0skj 0 are card 1959 xnstlt -instit t 2/2 te) 4 "SHOTIM I. S. RUO~r approAmations In the Xw&M mthod. Fix. tver. tela 2 a0,,5:908-912 NY I" (XIM 13:10) 1. politskmichookly Institut, "T. (lattice theory) 84617 8/181160/002/010/045/051 lit 0) BOI 91BO56 AUTHOR: Mashkovich. V. S. TITLB. Dipole Approximation in the Micro-theory of Crystals. I- Lattice Vibrations Taking in Consideration the Electron Dispersion IN FIRIODICAL: Fizika tverdogo tela, 1960, Vol. 2, No. 10, pp. 2629 -2636 TUT: X.- B. Tolpygo, in the Born theory of the crystal lattice improved by him, proceeded-frou the assumption that the potential energy of the crystal depends on the displacement and the electron dipole moments of ions. At the same time, he neglected the inertia of the electron dipole moments or of electron dispersion. In the present paper the electron dispersion for lattice vibrationa, the frequency of which is *&all com- pared to that of the electron transitions, is taken into account. Be- side#2 *sub-cells* are assumed to be crystal elements, which are con- sidered to be parts of the unit calls belonging to the nuclei. In the first part, the Hamiltonian of the electron system is set up in harmonic PAkrd 1/3 84617 Dipole Approximation in the Micro-theory of 3/18 60/002/010/045/051 Crystals. I. Lattice Vibrations Taking in B019/BO56 Consideration the Electron Dispersion approximation, after which the delayed interaction of the lattice vibra- tion~ with the electroaagnetic field characteris*d by the vector poten- tial I is investigated. For the perturbation operator 'HII in the Hamil- ii( + ) tonian of the system the expression HI - Oxp(-iWt) + h exp(iwt)(9) is obtained. With the aid of N for the wave function the expression is . v(+)*xp[_i~jo + O)tj + vk-)Oxp[-i((,)o - w)tj (11) is obtained, where V(�) j(njh(-�)j0~n/4(wo - Wn + W). Moreover, from the *equations of otionO of the electron dipole soaents and the equation of action of the : *ntors of same of the "sub-cello", the amplitude equations are derived. Finally, several properties of the coefficients of the two amplitude equations are discussed. The results given here represent a generaliza- tion of the theory developed by Tolpygo in the following resp*ots: 1~ lo assumptions are made about the existence of the potenti4l energy. 2 The electron dispersion is taken into account. 3) The difference Card 2/3 846!'? Dipole Approximation in the Micro-theory of $/lei /60/002/010/045/051 Crystals. 1. Lattice Vibrati-ons Taking in BOl9/BO56 Consideration the Electron Dispersion between the nucleus coordinate and the coordinates of the centers of mass are taken into account. 4) A zero dipole moment is assumed. 5) No assumptions art made as to the binding of the electrons in the ions and the approximationsof the wave functions. In a following paper, vibra- tions of dipole moments with frequencies lying within the range of electron transitions are to be investigated. The author thanks K. B. Tolpygo for discussion of the results obtained. There are 7 ref- erences: 6 Soviet and I German. ASSOCIATION: Xiyevskiy politekhnicheakly institut (Kiyev Polytechnic Institute) SUBMITTED: March 14, 1960 Card 3/3 P~l 3/056J60/038/03/22/03~ 3006/B014 AUTNORs Mashkovich, T. S. TITLEs -Electromagn*tic Waves in a Medium With a Continuous Inergy 3yeatrum ilkI PnIODICALt Zhurnal skeps,risentellnoy i t*or*tich*skoy fisiki, 1960, Vol. 38, Do. 3, PP. 906-911 TEM In the case of spatial dispersion it in possible to consider pol&ris&bility to be a factor of proportionality between polarization vector and field strength. The effect of spatial dispersion was studied by P*kar (Ref. 1) far the exciton #tat*. In the article under review, the author studies certain curr*ntl*ss state* and approach** the dependence of the polarisation vector on the field strength by using the p9rturbatiGa theory. go uses a modification of the Weieskopf-Wigner method similar to that employed by Born et &I. (Ref. 2). The Ramiltonian of this system in set up as the sun of the unperturbed R&miltonian R 0of the dissipative perturbation 91 and the electronagnotio perturbation 11. The wave function Card 1/2 82421 Electromagnetic Waves In a Medium With a 3/056 60/038/03/22/033 Continuous Inergy Spectrum. I B006%BO14 of the system in similarly composed. H ^A is determined from the interaction between electrons and lattice vibrations. It is assumed that when twO the system to in the ground stat*, and that the interferences of energy dissipation of the various states and the width of the ground state are negligible. ~(+)exp(-iwt) + ^(-)Oxp(iwt) , and the corresponding h steady-state solution of the wave function If' can be written down.. Next, the author studios the dop*ndonce of polarization on the electric field, and derives a number of relations. In conclusion, he studies the dispersion relations for the so-called kernel of polarisability, and dis- cusses the solutions of the Maxwell equations. There are 4 Soviet roftr- onces. ASSOCIATIONs Kiyovskiy politekhnicheakiy Inatitut (KiZov Polytechnic Institute) SUBMITTEDs September 3, 1959 Card 2/2 BANPADZF.,, R.V.; MSHMICHp V.S. PLapproximation in the tbeory of & diamond-typs, crystal Uttice. Lm. v7soucbsbeswo; Me zw*105-40 161* (KEM 14:7) 1e Kiyevskly politekhnicheekly institut. (Dipole moments) (Crystal lAttices) A, 7 25200 031 S/056/61/040/006/021/ ~ . B108/B209 (,#o/ /n -3) M Mashkovich, V. S. 0 R -TITLE: Electromagnetic waves in a medium with's continuous energy T L E IT spectrum. II PERIODICALt Zhurnal eksperimentallnoy I teoreticheakoy fisikior V. 40, PJMIODICA no. 6, 1961, 1803 - 1011 EXTI In T TEXTs In a previous paper (Ref. Is ZhETF, L8, 9o6, 1960), the author has derived equations for a electromagnetic field In a non-conducting medium erive 0 dd with spatial dispersion. The results are now applied to exciton states of a 'crystal. Calculations are made on the basis of the integro~differential 0, ,i,equation + T6 (r) + UT (r, r) Sk (r) ~r' 0. (1) 01 4ig Kke (r, r) (e) dr', (2) whioh automatically accounts for the additional conditions and requires n 0 1 Card 1/7 25200 5/05~/61/040/006/021/031 Electromagnetic waves in a ... B108/B209 the selection of the exciton wave functions; as the latter, the author used thos6 of S. 1. Pekar (Refs. 2,3s ZhETP, U, 1022, 1957; ZhETF, a, 117 6 1958).' In Eq. (1), J/o2j the polarizability'kernol is given by + Kel,,, (r, (0 1 ar W I R) (" I or, W) 10) (n I Oe (r) 10? (0 1 Ov. (3) hW - is. (W) Es + AW Is,, rot, 1(,'. (r, r,) = 0, (4) 730 where E0 is the ground-state energy and En that of the exnited'statel F_n is related to the lifetime of the state as usuall G(r) is the operator of the electric moment per unit volumel the operator "rot" indicates "curl". For waves in an infinite crystal, Sq. is transformed into Card 2/7 ........... 5 )0 S/o5y6l/040/006/021/0131 Electromagnetic waves in a ... B108 B209 Ke'. (r, r') K,",' + K,-ee (r, LI K ',, (r, r') :] ~ r� (k, a) x X, (21t)J Aw .. ) I t x (b, W, k. k. at) ex pA (r r') T- i2n (br b.'rj I dk; .(6) bb, E (k. - Es r� (k, a) :F WX :gw) - Ea t g+.Y, (b, W, k, W, g,, (b. k. o,) g,, (b', W, a), g- with the exciton quasi-momentum k and the vector of the reciprocal lattice. Taking into account that the generatrix of _k in (6) cannot be ara~ytic at the point 0, one may rewrite Eq. (1) in the form Card 3/17 25200 3/056/61/040/006/021/031 Electromagnetic waves in a ... B108/B209 (r) + 11,~ (r) + 4nr (r. r') 11,4 (r') dr- 0. (7) Wo a) (0, 0, a i .-al 0, -al ai a + a Wr g,, -Fr 7 W) )1.+*- 45'- 'The primed sum in (8) indicates that terms containing a singularity are 112 neglected. The wave function 2- is used for the case of k (TIX k a wave passing through a plane-parallel plate of a cubic crystal.)('-`~ is the kk. wave func~~n of the infinite crystal. -'04 ka k& k I -ka . ka k 1,2 1,2 1,2 3 3 3 'VVAN + 1), V= I ...... NJ a1,2 are the parallel surfaces of the plate, N the number of Card 4/7 25200 5/95 61/040/006/021/031 Electromagnetic waves in a.... B108YB209 unit calls across the thickness 1 of the plate. When the z-axis is per- pendicular to the surf aces of the plate, the integral-kernel has the form hy Pl K V F� (k, a) exp (:F i fk3buz + $ 24) (2:q bb' + It, (x x~ k,, (Y - Y') + (kibl, + k2b2.) (z - z') + 2:t (br-b'r') 1) x x Igt -, (b, W, k, k. at) exp (� ikabuz t - 9-V (b, W, k, i, a) exp (T ik3b3,zj I A, dk,,. (13) where k 'Tr./(z. + 1 ). In this case the equation of the field is glv*n by + (Z) + X (z, z', b, b'. a) 9(2') dz' = 0. (14) 2F W provided 9(z) lies in . O the y-direction. The.sum over(Y- concerns transverse excitors only, b nb n integer number) VZ 4yL21/ji 0; ' z Card 5/7 25200 S/056/61/040/006/021/031 rilectromagnetic waveB in a ... B108/B209 "Z (z, z', b, o', a) exp (2,t (bz b r- (k, a) g. (b, k, a) x x exp (ikz) (g. (b', k, a) exp ikz') -go (b' .- k, a) exp (ikz') 1, where f f 7,g. (b,k) f(nt kj 9 The solution of Eq. (14) has 0 C) k 3 x9y the form 9 (2) c, exp Ux,z), (16) where r are the roots of the equation g- (0, o, x, x,, a) r- -4- TI + 0 (x, a) o. (17) Card 6/7 25200 S/056/61/040/006/021/031 Electromagnetic waves in a ... B108/B209 Pinally, the absorption of an electroinag-netic wave with spatial dispersion is investigated, leading to the term 2i, 8,~*.(r) 8~-(r') dr dr'. where R y is the anti-Hermitean part of the kernel K x y There are- 7 Soviet-bloc references. ASSOCIATION: Kiyevskiy politeklinicheskiy Institut (ICiyev Polytechnfe Institute) SUBMITTE"D- January 11, 1961 Card 7/7 DUOUDE, V. A., MASHKEVICH, V. S., PRIMIOTIKO, A. F., PROKOPTA, N. F. , SGSKIN, 1% S. ONEWARON6 ffind:uced radiation in molecular crjstals." A four-level scheme for a quantum generator was discussed. It was shown that optics.I properties of molecular crystals provide a basis for the reali- zation of a quantum generator. The report presented to the 22th Conference on Luminescence (Nolecular luminescence and luminescence analysis) Minsk, 10-15 Sept. 1962. D2 2 12 /31 '2' 11. hk e v 4- c hY Condi ti~ns for the occ-,;rrel-11ce -,f si~at- crystals --,J zika tverdoCc te' a, 4 , no - 6 EXT The spatial d is.-je rsior. contained in the ocal re'- at ;-7)/4n is examMed usinC, PA, f K., (r') dr' (r, r') (E. Ej X x !(() G,,(r).n)(n C,.(r','O) (n G,,(r) 0)(0 Gv.-(r') n)-, Ell - EO Here C"L(r) is the solenoidal part of the amplitude of the Card 1 13 Conditions for the occurrence -Z 12 r -'Ih the frequency (J. P(r) is the -)ola7izatic) w ener_cy of the ground state, and s t e n e r y 3 f h e e x c 3 t 'p', is the probability, per unit o f me , o f it 4- 3-:. Z, t- 7 rl / interval of the frequency that correspor,,:s to szi:-tes u*---"---,-L C. ene=y 2 + and G(~'*' is the' oolarization ot;erator. e d e e 0 - is determine' b spatial disper340n - y H e r t: S e radius of the kernel cf -olari'zabiI4.ty ant4 the f -h-. . The s atial. dis,---arsJon of the !,-,cai or -Iil).11-.3c~- . L corresp~Dnds to the polarization causel ,-Y eXci1ta-.-:J:.-;. i t h 1 tr,at. these tViG Va:-4.U11t3 (Ii,cai and considerably froin one another. -.here is :-1-G for impurity states -ith lar--e rad-Ju s or t h I o c a e r-.-: In the case of spatial dispersion of *he nor.-I(J-~al excited states causing polarization .iust ljeion,~ to -0, ~ . , S)/ 1 must hold. This condition car, be a ectrum and i( as where 1(-80) 20. 1// --s -~ha Ll lifetime of the excitons with respect to the tia.-.3itiOnS t'~ Card 2/3 ConAitions for t1le Occurrerce ... states s + -tw N - - 0 S) k S " .11-er, exciton, Of he electrons tten y may j e 1) ex0iton band at suf,- - - end con5'.d6r4b!~, on the ,!cje,-,t,y of Probably spatial dis ~0*11 tem")eratu'res. c; 0 ") 'r, e 'De ra i or: Of the non-loc excep: al to t,-v "w ter:'Peritures. _1 t s lr'st"Lut f4ziki A21 USoR) Kiyev /Instit.t. of ~rx-rSSR, Kiyev) -ys:cs ;,-z 9052 Card 313 /~A# 1W211t 5/18 1/62/004/010/055/063 B102/B104 AUTHORS: Broude, V. L., Mashkevich, V. S., Prikhotlko, A. F., Prokopyuk, N. F. and Sookin, M. S. TITLE: Possibility of obtaining induced radiation in systems with electron vibrational levels PERIODICAL: Fizika tverdogo tela, v. 4, no. 10, 1962, 2976-2976 TEXT: A possibility of obtaining negative temperatures and induced radiation in a four-level scheme of molecular systems is discussed. The scheme (Figure) consists of the ground state (1), a vibrational level of the electron ground state (2), the first excited electron level (3), and the totality of all higher levels (4). 1"-4 is a transition due to light- quantum absorption, 4-3 a radiationless transition, 3-2 the transition used for obtaining the induced radiation and 2-1 again a radiationless transition. The lifetimes of the radiative transitions are T , 10-7 _ 10 -9s*c, those of the radiationlese transitions are k 'f" v/. r n r r has to be small for obtaining the induced radiation. Generation of Card 1/4 S/181/62/004/UlD/055/063 Possibility of obtaining induced ... B102/B104 2 C7 2,&,- coherent induced radiation begins if n -n 4 ax i, v r I-R where n n are 3 2 o 1 29 5 the mean numbers of molecules in state 2 or 5 per unit volume, V is the wave number of the 5-2 transition, v the halfwidth, H the reflection coefficient of the resonator mirror, I is the length of the sample, and ro is the lifetime of state 5 with respect to the 3-2 transition. n3 4 U K," N, where IV is the lifetime of state 3 with respect to all other transitions to lower states, K is the mean absorption coefficient on the region of the 1-4 transition, ILis the number of states 3 produced from one state 4, and N is the number of photons of the optical excitation 1-4 per unit of time and per unit of surface area. Numerical estimates for the anthracene molecule are presented. For K&2 cm 'r - 3-10- sec and 'r - 10-7sec one obtains N - 4-10 21 ca2sec -1 which can 0 be realized by means of an WOK-2000 (IFK-2000) pulsed lamp. If besides ,,Irr, n 39 N will depend on 'Al, not on Valone. This makes it Un "\ An I;o possible to draw conclusions as to the most effective form of luminescence spectrum to obtain, induced radiation. A system of layers of dielectric Card 2/4 3/1 a IJ62/004/010/055/06 3 Possibility of obtaining induced ... B1021D104 coatings with a certain R(&A) dependence induced radiation frequencies other than peak. Thus such a system can be used as figure. The most important English-langaage et al. Phys. Rev., 123, 765, 1961; E. G. 35, 759. 1961. allows of annihilating all a chosen one, where R has a an "antifilter". There is 1 references are: W. Kaiser Brock @t al. J. Chem. Phys. ASSOCIATION: Institut fiziki AN USSR, Kiyev (Institute of Physics AS UkrSSR, Kiyev) SUBMITTED: June 6, 1962 Card 3/4 S/181/62/004/010/055/063 Possibility of obtaining induced ... B102/BI04 I -%%~ M-3 -4 I - j I I --- I - 11,78' -1 Fig. Card 4/4 9/181/62/004/011/034/049 Dios/siol IUTBORj Mashkovich, V. S. TITLEs Absorption and dispersion of light in the region of exciton junctions PERIODICALt Fisika twerdogo tela, v. 4, no. 11, 1962. 5279 - 5285 TEXTv The effect of spatial dispersion on-ths, dispersion and absorption of light around oxciton transitions is studied for the case of weak xciton-phonon coupling. The Maxwell equations are solved by a method : eveloped previously (ZhETF, 58, 906, 19601 40, 1805, 1961). The effect of spatial dispersion increases with increasing oscillator strength of the transition, with increasing mean free time of-the virtual exciton, and with increasing width of the exciton band. This effect say be considerable, particularly at low temperatures. The spatial dispersion leads to a violation of the Kramers-Kronig relations when the seen free time of the virtual exciton is long enough. When linearly polarized light falls per- pendicularly onto a plane parallel plate, the width of the region in which the spatial dispersion becomes effective to small as compared with the width of the exciton band. Card 112 8/181/62/004/011/034,/049 Absorption and dispersion of lignt ... B108/B102 ASSOCIATIM Institut fiziki AN USSR, Kiyev (Physics Institute AS UkrSSR, Kiyev) SUBMITTEDt June 1, 1962 (initially) z July 3, 1962 kalter revision) Card 212 S/056/62/042/001/0k2/048 U B100102 AUTHOR: Mashkevich, V. S. TITLE: Electromagnetic waves in a medium possessing a continuous energy spectrum. III PERIODICAL: Zhurnal eksperimentallnoy I teoreticheskoy fiziki, v. 42, no. 1, 1962, 135-143 TEXT: The theory of electromagnetic waves In a crystal in the presence of spatial dispersion due to exciton states was applied to a number of problems in previous papers (ZhETr, je, 9o6, 19601 AQ, 1803, 1961). The solution of Maxwell equations for a nonconductive medium was presented in The pro agation of perpendicularly incident waves through a plate (cubic crystalT was examined in II without allowing for birefringence. The birefringence due to spatial dispersion is now taken into account. Using results and symbols of the previous papers and assuming optical anisotropy for a cubic crystal, the following relations are obtained for the amplitudes of incident, reflected, and transmitted waves: Card 1/4 Llectromaenetic waves in a medium... B104Y13102 R. I - 0% + Fl. D. 9. i20, exV iho Gs +(I + IFJI ' 01. + 0 + JF.)' (4). F.-=f,,ctgx,"l+f,,,ctgx,,j, G,=f,,/sinx.,I+f,,/sinx,,,I, XM / As (X2.1 - k2.) f is obtained from f by permutation of subscripts 1 and 2; K2 are n2 nl nl,2 the roots of the equation X9 + Y V + UP) + BI(IXXI ic. 0. B 4xVL'l I P..L IE (0. al) Es I/ U, As / W., E,, + Aw E (0, al), 5/05 62/042/001/022/048 Card 214 B/056/62/042/001/022/048 Electroma6,netic waves in v. medium. B100102 where mn denotes the eifective mass for the direction 9, Wpendicular to the plate; P allows for the local part of polarization; k n is the root of -1 2_ the equation , k it o. if M and m differ noticeably, n n 1 2 birefrineence will take place. The penetration of a plane-parallel plate by a wave incident at an arbitrary angle is considered. Restricting oneself to a semi-infinite crystal, the following generalized Fresnel formulas are obtained: f__ f .p (12x4) f-- R,w = 4, Is +-+ 14 it-2- to + e- p(12xj) I-,,- f (14). D,, IL44PS 91 q2 94 exp I i (x,, A.) 11 x PI_ A- P; x + exp (21M.4 I- /~+I- 14 Card 3/4 S/056/62/042/001/022/048 Electromagnetic waves in a medium... B104 B102 -11 Lhe longitudinal components of the electric field of a light wave are calculated, and the results are compared with the corresponding results -f S. I. Pekarts theory (ZhETF, .3A, 1176, 1958). The latte~r is criticized -ri connection with the case of oblique incidence of a longitudinal and a .r-ansverse wave field. There are 11 references: 10 Soviet and 1 non- iviet. ..~__-,OCIATION: Kiyev skiy politekhnicheskiy institut (Kiyev Polytechnic Institute) ,11*: -ITTED: April 25, 1961 10 Egg 9-9~ AratM LIA-1 PIP -S 'Eff wl~ MASHUVICHP V.S. [lbahkovych, V.S.) A 3,aster based on Raman scattering. Ukr. fiz. zinw. 8 no-91 1032-1035 5 163. Nonlinear optical properties of a threo-level system in a resonator with several modes, Ibid.slO35-1039 (MIRA 170) 1, Institut fiziki AN UkrSSR, Kiyev. -_ , I I I : .. - ~ ; ~, -: 1 i, - I , . ~: - .: . I ~ .~ - - -: 11 . - ~ ~ , . . - ? --., Z 7 ' I -- - - =-,m - . "- 1~ - L 33166-66 EWT(1) IJP(c ) JV-W/GG ACC NR, AR6Oi6i�~---- SOURCE CODE: W(5o58j65/OW/OL1/DO30/DO31- 27 AUMOR: Mashkevich. V. B.; StrashalWya.-14. I TITLE: Pogilble manifestation of additional waves in the reflection of 1 from crystals SOURCE: Ref. zh. Fizika, Abs. 11D234 REF SMM.: Tr. Komis. po spektros~x .211. AN SSSRf t- 3, VYP- l.- 1,964., 448-453 Topic TAGS: light reflections exciton absorption# refractive index, cadmium sulfide AMTRACT: Xt Is indicated tbat usually the manifeefttlon of additional ligft veves in the region of e=iton absorption of the crystal be& been considered only in con,- nection with the passage of two waves tbrowgb a thin plate. At the saw time, adA'- tional. vaves can alvays greatly influence the reflections too. Zspecia.1.1y ebaracter- istic is the case Aen the refractive indices of the two myes satisfy the relation mf m r?l > 0. O= the additional vave can greatly influs=* the pbase of the re- f1wted vwm. The CdS crystal is considered " an examWA. [Translation of abstractil SUB'CODE: 2D/ 6 ACCESSION NR: AP4041706 S/0181/64/006/007/2037/2046 AUTHOR: Vinetskiye V. L.; Mashkevich, V. S.; Tomchuk, P. M. TITLEs Theory of stationary radiation induced by interband transi- tions SOURCE: Fizika tverdogo tela, v. 6, no. 7, 1964, 2037-2046 TOPIC TAGS: laser effect, laser emission, laser pumping method, stimulated emission, transition frequency ABSTRACT: A kinetic equation method developed by the author for the analysis of stimulated emission (UFZh v. 8, 918, 1963) is used to de- termine the parameters of the singular modes at which laser action can be achieved. These parameters are then used to determine the threshold value of the pump signal. It is assumed that only direct transitions are effective, the electron and hole bands are spherical, the electrons and holes have equal effective manses, each band is in Card 1/2 ACCESSION NR: AP4041706 statistical equilibrium, and the system is spatially homoqeneous. it is shown that an important factor in the feasibility of IaBer ac- tion is the spacing of the singular modes, and monochromatic emission is possible in principle if the spacing is large. Future plans call for investiqations of induced emission for system with impurities and the use of x-rays or gammia rays for pumping. Orig. art. has: 56 formulas. ASSOCIATION: Institut fiziki AN UkrSSR Kiev (Institute of Physics, AN UkrSSR) SUBKITTED: 24Feb64 ATD PRESS: 3076 ENCL: 00 SUB CODE: EC , QP MR REP SOVt 004 OTHER: 004 Cord 2/2 PASIBC.-I'VICIII V.S. [Mas~Lcevyoh, V.j. j Laser with two Vpes o' active centers. U~x. fiz. zhur. ~ n-l-.1-1: 1260-1263 N 164. (: az LA l'i : ~, ) 11 1. Institut fiziki A:i "iyov. ACCES=X Us. AM12027 3/0185/64/009/001/0014/0025 I AVMRs Dwyakivalkwey, as Ya. I X&shk*V*Qh' VO 3 Tr=s Theory of stationary madiallon of a homogeneous mWaten in -9 multimode resonator, 1. Dvadom of ndation on the aft SOMM MMSYIWIWy AWdu" --hunal. V. 9. no. 1. 19&. 14-25 MPIC TLOSs laawo maser, resonator, resonator nods, laser theory, rAng, multi- mods resonatore IdwUo equat4ons -ABSTUCTs The present waric was wulertaken to mays the proUss, in laser theory, of determining the nodes at which generation Ah*WA occuro In previous work by one of the authors It was shown that, by using the method of kinetic equations, a nwibor of true results can be obtained in the case of a stationary reglme; he succesded in investigating nonlinear properties during weak swings and in proving the existence of a sharply expressed threshold of generations. In doing so, a large noiber of modes and. since the field was considered in a quantm mechanical sense, *cutaneous radiation won consistently taken Into account. The present work continues the, Investigation. Using- the nothod of kin*Uo equations the Card 1/2 AC4==N Us AP4=27 authors develop the theory of the stationary radiation of a homogeneous sYstem in & resonator where there is a great nwbar of resonator nodes within the width of the radiation line. (Because of the "Ume ooaplwdty of the problem of heterogeneous systems, invosugstdon of Seneous systaims Is a necessary step, ev thou& It must still be detemined iftether a laseroalkn be gonsidared a hanogensous system.). Tas finding that the intenatir of radiation of the resoator nods is a function of the swing In reglops of weak and strong swings is a real st4V forward %hich per- mitted obtaining vow deta" Womation on the PrqPwties of the syst4m and the geners- radiation. It is shown that it the mabar of nades at *Lcb tion of induced radiation oomrs Is niall In comparison with the amber of modes, there in a pronounced thredwId. value of the amino lbe w14th of the threshold region is found. Or1g. art. has 85 fanolas. Insty0tat fis~ AN UkrLSR, Ziff (ISBUtlate of ftsiose AN MQM) SMTM OWAY63 M (MIX: PA. AS Card 2/2. DM ACQ& 147ob& --NO MW XN& 002 2=3 00 0=3 0" ACCESSION MR: AP4017404 S/0185/(A/00/00VO226/0229 AUTHOR: MshkewV*ch, V. S- TITLE: Radiation of the second optical harmonic SOURCE: UkrayIns'ky*y flz"chny*y zhurnal. v. 9. no. 2, IWA, 226-229 TOPIC TAGS: electrodynamics, loser, quantum mechanics, crystal radiation. optical harmon1c, perturbation analysis. combinatorial scattering, phal ABSTRACT: The high paier levels bbtained from present day lasers create condi- tions favorable to the generation of the second optical hqrmonIcs In crystals. The classical theory of electrodynamics Is not applicable because of relatively high second harmonic power levels and because the reverse process, I.e. recombine- tion of the second harmonic radiation to give the fundamental frequency. Is non- singular (I quantum of the second harmonic radiation yields 2 quanta at the funds- mental and vice versa). Hence, a quantum mechanical analysis becomes necessary. The simplest model, having only-one mode at the fundamental frequency and one mode at the second harmonic, Is assumide" For a stationary sptem, with spontaneous radiation at the second harmonic frequency, the condition under which the second harmonic radiation offlclemyg 0 1 IF-0- appnolmately 100% Is *~ " &%,c Cord 1/3 ACCESSION NRS AP4017404 where a, and a are losses associated with the actual propagation modes of the fundamental 8:3 the -second harmonic components, respectively. The Inequality (1) assume$ very large values of N,. the pump level at the frequency and the mode of the fundamental component. if q, Is the -, 6er of quanta In the fundamental W -1- and If q, >> I then the assumption of large N, simplifies to: jV, 3, 1! 28' (2) where 8 Is the probability of transition of two quanta of the fundamental mode Into I quantum of the second harmix (c mode. Thus. when the basic Izequality (1) is satisfied and when the external losses at the second harmonic fr uency are low, the pump levels which satisfy (2) giv*4 )- 1. The classical approach gives the erroneous answer that 17 -%s, I can be &chi owed I ndependent I y of the va I ues of al and c%2. Perturbation a lysis of the spontaneous stationary system with the above assumptions shows that It Is stable. When the refractive Indices at the fundamental and second harmonic frequencies are equal, a maximum transition pro- bability 8 rejj!ts tnd, for Items realistic parameters, the Inequality (2) gives N >> O.S x 10 oc" . This level Is achievable with ruby loser radiation. It Is t9 author's opinion that values ofo7g= I were not achieved untl I now because the bas I c requ I remant as expressed by I nopm I I ty ( I ) was not understood and not fu I - f I I led. UmInailon of an Indoced redlation systain shows that the generation of the 9 hennonic Is awlepus to con6inatorlel scatterinjo The basic diffl- W ACCESS I ON KRt AP1401740 culty arises from the fact that the coherency volume Is limited by the free path length of a phonon. Indicating the requirement of low tempetratures for Induced generation of the a PoW harmanic. Orig. art@ has: 25 formulas. ASSOCIATION: INSTY*TUT F1 AN UASR, WW. (institute of "sics, Academy of Sciences of the Ukrainian SSA) SUBMITTED: O8Oct&3 DATE ACIS 19PAr" FACI.S ad sue COUS op NO R9F SWs 003 OTHFAs 003 Card 3/3 '~. --: ;I - ~'.. I...,- .- . -- I- -- w :- - - - .- : 11 .~ ~ I ., . Z- - - --- - - ~z : -'- -, Z-, I - --- - - - -, -- -- . . , ~ . -~ , , , ~ ~7 ~~ . - , '- I .~ - ~- 1. . . - - ig, ~ :a~ If z - - ,- -,--.,cy,7-,- f- jz~- ~- tT- -?~ i . , .- - j. FF-_ - - - - - ---- - . . . - . - -1 .. - - .- I . . 1:.... ., - w, .: - -. . . . . :~ ~ -Z.~ , -.1 - ., . - - - - - N'. - . . . . . :, ~w% , ~ .: ;l . - .- ! ~ t, .. . ~ I I . . - i. . I . 1 .1 1 .. . I I .- x - . . - . G I ; - . . . . I aiw- i. rld -6 ... I ~ - 11 , 1. , I I I. I . . : - -,i . . I- i- . -, . . :1 ;7,; -;~;: - : .., .: q - ~ -1. :-_ - - . '. L , -; .- ~~ ~ -: "-,.- ,, ~,-- --:,- --- . ,.., - - ~ -! ~ ~a 1, ml 1 1, - . - " 11 - o., - -, .4 Wall RIMPIN . )., rR I . Z_g nl MOXV t W-PM -4, P; Pi-- WN 1m, VV 600 21-rz 10 41t ~W7 A -- ~ --- CV.-- omit, -my r7t AL, altIL f Virr j;RX AS AK I'A r r~i - -w-ard, Ac _M 9- P-1: ..,.q ~_N M_ MWN ROME: i_ PEW-- MW W_e7 -61 wt J;717 '&VA it wto M UZI OM 1, WtoW.:. a 7~~ Z~AS_W_ -5. 95i Ut 'Ef-Ru z 'Ra 1, ,r I . M -- -:- - --. - - . - 1 -1 i - . . . - I I 7 - -- -7,-- - -- IN, -- - - -- , , '. I- , - 7 . -- 1: NPR 7 sommosimalM. M ;--_7 --- - - ~ . ~. .. . ~ i ~- - . - . . : . ".-;. -.- i --I - - -, - ". -I ~ . - -,-- . I .. ~ ~ 1.- -1 !-.-- Llll -- , !:. - - - - ~ 7A.11- - i -.' , . ~. ~~:, ..... :: ~- -71 - .1 ~ .. d.,.J.- 1 . .. I . . - . . I I-. . . I ! I - -t ~, 1. -, -, ~~: ~ -4 -~-. " .- w . I I ... . r - I - . I . . ~: ~4---;7~ - --- - - - -.-' -. - - - -- --', -;, -.; , - - ,, , . I -: 7 .. - I . ~ ~ %~* - ~ -:. ~ r , ", - ~ - I !!!!. ~. . . . . ., 71 !;~ -7 '1 ~- 4,--- , :- I -t-'L & ~ Q. VINF.TSKIY, V.L.,, MASHMV1,211 V.S. ~~ensration of la3er recliat-'.on in direrc tranaltiong -In $1 meWconductor. Fiz. tvor. tela 7 no.6-1898-1899 Js 161,. (MIRA 18t6) 1. Tnetitut flzlki AN UkrSSR, Kiyev. I'M ton miw V~ MORT M W97 OX _1 R ~Ra I A2 MaMMMIM z-N R, OP- -A, R~ M M; WIT RIMMME, wo 1j", ~ ow I W~_011111 0 ~W_ s MAIMISHKOf I*A. [Ma-ruchko., ...0.1; RASUKEVIC, Gsneration of the soo-ond optical ha=outa in a laser -Mts fiz. zhurs 10 no.301i-322 Kr 165. 1, InOtitut fizJ-ki AN Ukr3SR, Ki."v. -or, witii riaisilon of spr* A-11 MARUSHKOv I.A. I jgmmvICHC V.S. - "WmlfW~ Idw width of induced Raman scattering, Opt* i spairtr. 19 no.U136- 1 138 A 965- (KMA 1818) Apir., a SpOctria P. The A--- 0- w AIDA if do 2- 'y ig 'Al Mgt RMS 3Yn,--- lk, L 32632-66 HD/E (1)/EEC(k LW W-T ACC NP, AP601882o SOURCE CODE: UR/0056/66/050/005/1410/11414 .,A7LJniOR: 14ashkevich, V. S.; Vinetskiy, V. L. -1 - ORG: Institute f Ph sics, AcadeaW of Sciences Ukrainian SSH (Institut fiziki, oi- !nauk Ukrainskoy SS137 f TITIX: Role of absorption by free carriers in a semiconductor laser SOURCE: Zh eksper I teor fiz, v. 50, no- 5, 1966, 14lo-1414 TOPIC TAGS: light absorption, 1zxMM2WW% charge carrier. semiconductor laser, carrier density, laser emission, photon. exciton, laser pWTing ABSTRACT: The authors present a consistent analysis of the interaction between radiation and the medium in a semiconductor laser whose characteristic parameters without allowance for absorption by free carriers were determined by them earlier (FTT, v. 6, 2037, 19a) - It is shown that when absorption of photons by the free car- riers is taken into account,the kinetic equation for the radiation-medium system can have three solutions corresponding to different carrier densities. Only two are stable and only one of these gives stable laser emission. The analysis is restricted to the simplest case of interband transitions in an Impurity-free semiconductor, neg- lecting the binding between the carriers and the excitons, although the latter assump- tion turns out to be in disagreement with the actual physical situation. The stable laser solution is obtained in the case of weak absorption by the free carriers, and a criterion for the realizability -f this solution to derived The threshold pump ener- C,,d 1/2 L 32632-66 ACC NRI AP6018820 gies of the different solutions are found. The second stable solution, which does notl correspond to a laser mode, and the unstable laser solution, occur when the carrier density is high, so that the screening of the electron-hole gas becomes appreciable. The results indicate that when attempts are made to obtain laser action in a semi- conductor by app W ng excessive pump power, there in the danger of producing condi- tions corresponding to one of the additional solutions. This is borne out by some recently published data (G. Burns and M. J. Nathan, Proc. I=, 52, &2, 1964). Orig. art. has: 1 figure and 20 formulas. [021 SUB CODE: 2D/ UMM DATZ: 07Dec65/ OPAG REF: 007/ OTH FJW: 002 / ATD PRESS: ,5'e 2 67 L 45861-66- EWT (1) /EEG W -2/T/-EWP.(k) VIG/GD ACC NRt AT6015142 SOURCE CODE: UR/0000/66/000/000/0214/OZZ7 :AUTHOR: Vinetskiy, V. L.; Kolychev, N. N.; Mashkevich, V. S. 'ORG: Institute of Physics, AN UkrSSR (Institut fiziki AN UkrSSR); Institute of Semiconductors, AN UkrSSR (Institut poluprovodnikov AN UkrSSR) ;,TITLE-. Theory of laser r diation from impurity-band transitions SOURCE: Respublikanskiy seminar po kvantovoy elektronike. Klvantovaya elektronika ~(Quantum electronics); trudy seminara. Kiev. Naukova dumka. 1966, 214-227 TOPIC TAGS: laser. solid state laser, semiconductor laser, IlLser theory) iA-5f *V-- Rf? 0i#9 7-,oo A*4 IfnpuRory 43AAlo ABSTRACT: The semiconductor laser operation based on radiative transitions of current carriers from impurity-band state to bound state is examined by the method of kinetic equations. A semiconductor having M identical impurity centers with a 11evel in the forbidden band in considered. Pumping drives the electrons from the !valence band into the conduction band. Electron-hole recombination takes place at* Ilevels. Hole capture by an impurity level in accompanied by radiation of a photon. lKinetic equations and a neutral -condition equation are set up. Solutions for the case ACC NR, AT6015142 iof acceptor and donor centers (Boltzmann distribution and strong degeneration in the hole band) are given. Absorption by free carriers is allowed for. This special feature of the impurity-band laser is noted: In some cases (medium pumping), populations of m, p, n levels and generated frequency vary when pumping produces 1 !higher -than-threshold number of electrons (holes) the number of quanta radiateC iby the special mode per unit time increases with pumping in a slowe r-than -linear manner; this deviation from linearity is pronounced with '0 approaching (m is the number of electrons at impurity levels; p is the number of holes in the valence ,band; n is the number of electrons in the conduction band). This feature is due to them absence of thermal equilibrium between the impurity and the band. Orig. art. has: ~2 figures, 80 formula@, and 2 tables. ISUB CODE: 20 / SUBM DATE: 12Feb66 / ORIG REF: 006 / OTH REF: 00 1 Cad Z/2 T, o1059-67 EWr(I)IT TJPW GI) ACC Nit, AT6015131 SOURCE CODE: UR/0000/66/000/000/0034/0076 AUTHOR: rushko, I. A.; Mashkevich, V. S. ORG: Institute of Physics. AN UkrSSR (Inatitut fiziki AN UkrSSR) TITLE: Method of kinetic equations in the theory of generation of SOURCE: Respublikanskiy seminar po kvantovoy elektronike. Kvantovaya elektronika, ~(Quantum electronics); trudy seminara. Kiev, Naukova durnka, 1966, 34-76 TOPIC TAGS: laser theory, solid state laser, kinetic equation ABSTRACT: 1. Deduction of kinetic equations from a density-matrix equation for them case of generatian of the second optical harmonic. Only stationary conditions of generation and only the process of frequency summation are considered. The analysis is made in the first nonvanishing approximation of the disturbance theory; contribution of multiphoton processes is neglected. The kinetic equations are: 2m j- B V [~2 Q, + 1)(j! + 1) + 1)Wo?. 6 (E, + E. - Ej) cg,'Wo + JV. .91, AW -F8Aj1(i2+ Oqil;?i -~24i'+ 1)(4-it+ 1)1 . d. a L 01059-67 ACC NR1 AT6015131 Applicability of these equations to near-stationary conditions of generation is briefly discussed. 2. Generation of the second harmonic in a plane-parallel slab. It is clarified which field vector potential should be used for calculating the nonlinearity B in the above kinetic equations. In each particular case of solving the kinetic equations, construction of orthonormalized solutions of the Maxwell linear equations is required. Kinetic equations and total -quanta -number equations for the second- harmonic generation in the slab are derived. From them, this formula for efficiency %( r) is derived: -k= 4 + P - 20' (e2 + q2 _. The second-harmonic intensity in the NA&I N transmitted and reflected light dependent on the angle of incidence (formula given) is convenient for determining the degree of agreement between the calculated and observed data. 3. Line shape in the second-harmonic generation with a speoified pumping at fundamental frequency. The above generation case is also used ior investigating the line shape. An integral equation describing the time shape is solvable only in two particular cases: (A) Gaussian curve (weak and strong generation regions); and (B) Lorentzian curve (weak generation). 4. Second- harmonic generation in the laser resonator. The harmonic generation depends on the nonlinearity B, photon density q, in the beam, and the lose ratio at fundamental and harmonic frequencies. Hence, an efficient harmonic generation can be achieved by ACC NRs AT60IS131 placing the nonlinear crystal into the laser resonator. The generation efficiency is qual to a ratio of the harmonic power to the dominant -mode -plus -harmonic power: k= To find the effect of laser pumping ~6 27B,?,(-l+as)+cLja, i ion the harmonic efficiency, the dominant-mode equation is solved for these cases: j(A) The near above-threshold pumping region for which this condition holds true: I ! - 27BB, nllp > 8BB. B. nil at. (m, - nil); (B) The pumping region in which this 7 a") - 0 condition i a satisfied: 104B. (m, - nil) - 2B8, n"12 < 8B, B. nil at, (In, - nil). (C) The at rong 0 - 11) Ills> 1). pumping region with this condition satisfied: I- B" (m, 2BBn 8TIB, nil a, (m, - n' MI_nII