1 / 10

Quasi-phase matching t ransient SRS generation

Quasi-phase matching t ransient SRS generation. Nikolai S. Makarov Saint-Petersburg State Institute of Fine Mechanics and Optics (Technical University). Victor G. Bespalov Russian Research Center "S. I. Vavilov State Optical Institute". Principle of quasi-phase matching.

yuval
Download Presentation

Quasi-phase matching t ransient SRS generation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quasi-phase matching transient SRS generation Nikolai S. Makarov Saint-Petersburg State Institute of Fine Mechanics and Optics (Technical University) Victor G. Bespalov Russian Research Center "S. I. Vavilov State Optical Institute"

  2. Principle of quasi-phase matching Nonlinearity (2) Nonlinearity (3) Raman active medium 2

  3. System of transient SRS equations  – wave mismatching, g – steady-state Raman gain coefficient, i – frequencies of interacting waves, T2– dephasing time, q – phonon wave, Aj– complex wave amplitudes, z=z’+t’/c, t=t’. 3

  4. Principle of quasi-phase matching at SRS -Generalized phase =2p-a-s-(ka+ks-2kp)r, where ki – is the wave vector of interacting wave, that describes the direction of energy conversion “pump – Stokes – anti-Stokes”, on passive layers input (0, 2) and active layers input (1, 3) do not practically change, that in a final result provides a realization of quasi-phase matching conditions. (3)0 (3)=0 4

  5. Quasi steady-state SRS pulse25Т2 (Т2=0.203 ns,pulse=10 ns). - It is possible to create conditions, at which anti-Stokes conversion coefficient reaches ~25% and the anti-Stokes wave intensity is practically compared to Stokes wave intensity 5

  6. Highly transient SRS pulse<<25Т2 (Т2=0.203 ns,pulse=25 ps). - The efficiency of anti-Stokes SRS conversion much depends on a ratio of dephasing time T2 to pulse duration 6

  7. Optimum ratio of input Stokes/pump intensities - There is an optimum value of input Stokes/pump waves intensities ratio. -This dependence can be approximated asIs/Ip,opt=0,1359g-2,6146 7

  8. Critical pump wave intensity - There is a critical value of pump intensity. -This dependence can be approximated as Icr.p=0.4Δ/g 8

  9. The conversion efficiency can reached more than 25% • The efficiency of anti-Stokes SRS conversion much decreased with increasing of a ratio of dephasing time T2 to pulse duration • For each medium there is an optimal ratio Is/Ip, at which conversion efficiency is maximal • For each medium there is a critical value of pump intensity Conclusions 9

  10. J. A. Armstrong, N. Blombergen, J. Ducuing, P. S. Pershan, “Interaction between light waves in a nonlinear dielectric” Phys. Rev., 127, pp. 1918-1939, 1962. • R. B. Andreev, V. A. Gorbunov, S. S. Gulidov, S. B. Paperni, V. A. Serebryakov, “About parametrical effects at SRS generation of higher components in gases”, Quantum Electronics, 9(1), pp. 56-60, 1982. • A. P. Hickman, W. K. Bischel, “Theory of Stokes and anti-Stokes generation by Raman frequency conversion in the transient limit”, Physical review A, 37(7), pp 2516-2523, 1988. • J. J. Ottusch, M. S. Mangir, D. A. Rockwell, “Efficient anti-Stokes Raman conversion by four-wave mixing in gases” J. Opt. Soc. Am., B 8, pp. 68-77, 1991. • Makarov N. S. (Scientist supervisor – Bespalov V. G.) “Generation of anti-Stokes SRS radiation in conditions of quasi-phase matching”, in book “Problems of coherent and nonlinear optics”, pp. 180-190, 2000. • Bespalov V. G., Makarov N. S., “Quasi-phase matching anti-Stokes SRS generation”, Opt. & Spectr., vol. 90, No. 6, pp. 1034-1037, 2001. References 10

More Related