Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download storing, retrieving, and processing optical information by raman
Document related concepts
Transcript
XXIX conference on plasma physics and CF, February 25 – March 1, 2002, Zvenigorod STORING, RETRIEVING, AND PROCESSING OPTICAL INFORMATION BY RAMAN BACKSCATTERING IN PLASMAS Dodin I.Y., *Fisch N.J. IAP RAS, Nizhnii Novgorod, Russia, e-mail: [email protected] * Princeton Plasma Physics Laboratory, Princeton, USA,e-mail: [email protected] In the experiments on “trapping” light pulses by means of electromagnetically-induced transparency [1], quantum effects are necessary for providing the possibility of recording and retrieving optical information in nonlinear medium [2]. In the present paper, we theoretically demonstrate the possibility of performing similar effects in purely classical media, namely, in cold plasmas. By means of stimulated Raman backscattering, the information about the structure of the pulse propagating in a cold plasma, can be recorded in the form of spatial profile of slowly propagating Langmuir wave. Recording is provided by nonlinear interaction of the information pulse with a counterpropagating short laser pulse producing a beating wave resonant to electrostatic plasma oscillations. Langmuir wave can sustain its structure on time scales large compared to the duration of the initial pulse, which provides the possibility of storing optical information in plasmas. In the next act of scanning the plasma by another short laser pulse, the stored information is retrieved into the secondary electromagnetic pulse generated by means of Raman interaction, which inherits the structure of the initial signal. The recording and retrieving procedures could be used for storing and processing analogue information, constructing the shape of short electromagnetic pulses, and for diagnosing strong Langmuir turbulence in cold plasmas. References [1] S.E. Harris, Electromagnetically induced transparency, Phys. Today, 1997, 50, 36. [2] D.F. Phillips, A. Fleischhauer, A. Mair, R.L. Walsworth, M.D. Lukin, Storage of light in atomic vapor, Phys. Rev. Lett., 2001, 86, 783. Authors: Dodin Ilya Yevgenyevich, Russia, Nizhnii Novgorod, IAP RAS, e-mail: [email protected] Fisch Nathaniel J., USA, Princeton, Princeton Plasma Physics Laboratory (PPPL), e-mail: [email protected]
