Regensburg 2010 – wissenschaftliches Programm
HL 60.19: Poster
Donnerstag, 25. März 2010, 18:00–20:00, Poster D1
Four-Wave Mixing in Gallium Selenide (GaSe) with a cw HeNe Laser — •Martin Baaske1, Lothar Kador1, Kerim R. Allakhverdiev2,3, Tarik Baykara2, and Eldar Yu. Salaev3 — 1University of Bayreuth, Institute of Physics and Bayreuther Institut für Makromolekülforschung (BIMF), 95440 Bayreuth, Germany — 2Marmara Research Centre of TÜBITAK, Materials Institute, P. K. 21, 41470 Gebze/Koçaeli, Turkey — 3Azerbaijan National Academy of Sciences, Institute of Physics, 370073 Baku, Azerbaijan
Quasi-degenerate four-wave mixing (FWM) experiments have been performed on the layered chalcogenide semiconductor gallium selenide (GaSe) with a 15 mW cw HeNe laser. Since the band gap of this material is close to the photon energy of the laser, its third-order susceptibility χ(3) experiences very strong resonance enhancement, so FWM signals can be readily detected with a setup adapted from . The laser radiation is split into three parts, two of which are frequency-shifted with acousto-optic modulators (AOMs) by ν1 = 70 MHz and ν2 = 110 MHz, respectively, and focused into a thin GaSe crystal. The generated FWM signal is superimposed with the unshifted laser beam on a fast photodiode, generating a beat note at 2 ν1 − ν2 = 30 MHz, which is phase-sensitively demodulated using standard radio-frequency electronics. The FWM signal of GaSe is analyzed as a function of temperature.
 A. Sherman et al., Opt. Lett. 34, 49 (2009).