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Intersubband electronic Raman scattering in narrow GaAs single quantum wells dominated by single-particle excitations

Takeya Unuma·Kensuke Kobayashi·Aishi Yamamoto·Masahiro Yoshita·Yoshiaki Hashimoto·Shingo Katsumoto·Yasuhiro Iye·Yoshihiko Kanemitsu·Hidefumi Akiyama
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Abstract

We measured resonant Raman scattering by intersubband electronic excitations in GaAs/AlAs single quantum wells (QWs) with well widths ranging from 8.5 to 18 nm. In narrow (less than 10 nm) QWs with sufficiently high electron concentrations, only single-particle excitations (SPEs) were observed in intersubband Raman scattering, which was confirmed by the well-width dependence of Raman spectra. We found characteristic variations in Raman shift and line shape for SPEs with incident photon energy in the narrow QWs.

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Takeya Unuma, Kensuke Kobayashi, Aishi Yamamoto, Masahiro Yoshita, Yoshiaki Hashimoto, Shingo Katsumoto, Yasuhiro Iye, Yoshihiko Kanemitsu, Hidefumi Akiyama. 2004-06-08. Intersubband electronic Raman scattering in narrow GaAs single quantum wells dominated by single-particle excitations. https://doi.org/10.1103/physrevb.70.153305

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