Femtosecond coherent spectroscopy of four-wave mixing and photon echoes in a GaAs/AlGaAs heterostructure at room temperature

• Published in: Bulletin of the Russian Academy of Sciences. Physics 2012-03, Vol.76 (3), p.290-294
• Main Authors: Ivanin, K. V., Leont’ev, A. V., Lobkov, V. S., Safiullin, G. M., Samartsev, V. V.
• Format: Article
• Language: English
• Subjects: Aluminum gallium arsenides; Echoes; Electron gas; Electron spin; Four-wave mixing; Gallium arsenide; Gratings (spectra); Hadrons; Heavy Ions; Nuclear Physics; Physics; Physics and Astronomy; Proceedings of the XI International Readings on Quantum Optics; Room temperature; Semiconductor crystals; Spectrum analysis; Spintronics
• ISSN: 1062-8738; 1934-9432
• DOI: 10.3103/S1062873812030124

The results from experiments employing coherent femtosecond spectroscopy in a layer of two-dimensional electron gas at the boundary of the GaAs/AlGaAs heterojunction at room temperature are presented. The decay curves of primary femtosecond photon echo are obtained. The decoherence time in two-dimensional electron gas depends strongly on the power of the exciting pulse and varies from 36 to 54 fs. The dephasing time is studied for the first time as a function of the power of exciting pulses at room temperature. It is established that this dependence obeys the law T 2 ∼ N −0.22 , which differs from the typical law T 2 ∼ N −1 for unscreened electron-electron interaction in semiconductor crystals. Analysis shows that electron-phonon interaction plays an important part along with electron-electron interaction. The induced spin gratings in the GaAs/AlGaAs heterostructure are studied with an eye to their possible application in spintronics.