Effect of quantum-well confinement on acceptor state lifetime in δ -doped GaAs/AlAs multiple quantum wells
Effect of quantum-well confinement on acceptor state lifetime in δ -doped GaAs/AlAs multiple quantum wells
复制标题
量子阱限制对 δ 掺杂 GaAs/AlAs 多量子阱受主态寿命的影响
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
M. Steer
中科院分区：
文献类型：
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作者：
W. Zheng;M. Halsall;P. Harrison;J. Wells;I. Bradley;M. Steer
利用远红外时间分辨光谱，我们研究了量子阱限制对井中心 Be δ 掺杂的 GaAs/AlAs 多量子阱中浅受主态寿命的影响。低温远红外吸收测量清楚地显示了由于 Be 受主态从基态跃迁到前三个奇宇称激发态而分别产生的三个主要吸收线。研究发现，激发态的寿命随着量子阱宽度的减小而单调缩短，从体中的 350 ps 减少到 100 A 阱中的 55 ps。我们认为量子阱限制对区域折叠声声子模式的影响增加了声声子辅助弛豫的受主内散射率。
Using far-infrared time-resolved spectroscopy, we have investigated the effect of quantum-well confinement on the lifetime of shallow acceptor states in GaAs/AlAs multiple quantum wells with Be δ-doping at the well center. Low-temperature far-infrared absorption measurements clearly show three principal absorption lines due to transitions of Be acceptor states from the ground state to the first three odd-parity excited states, respectively. It is found that the lifetime of excited states monotonically reduces with decreasing quantum-well width, from 350 ps in bulk to 55 ps in a 100 A well. We suggest that the effect of quantum-well confinement on zone-fold acoustic-phonon modes increases the intra-acceptor scattering rate of acoustic-phonon-assisted relaxation.