掺铍GaAs量子阱的光致荧光

PHOTOLUMINESCENCE OF Be-DOPED-GaAs QUANTUM WELLS

测量了掺铍的,阱宽约为10nm的GaAs量子阱在4.2K的光致荧光。掺杂浓度分别为1×10^(17)和5×10^(18)cm^(-3)。测量结果表明:对于无规掺杂,局域在阱中心的铍的状态密度与导带电子从n=1量子能级到阱中心中性铍的跃迁概率的乘积大于对应于介面铍的乘积。另外,实验结果也表明:当掺杂浓度升高时,由于带隙收缩的影响,阱中心铍的电离能减小。

The photoluminescence of Be-doped GaAs quantum wells with width of 10 nm was measured at 4. 2 K. The doping concentration is about 1 × 1017 and 5 × 1018 cm-3. The results showed that the product of the density of states of acceptors and the probability of transition from conduction subband n=l to neutral acceptors at the well center is larger than that near the interface of GaAs and AlGaAs. In addition, the ionization energy of acceptors is decreased as doping concentration is increased. It is due to band-gap narrowing with the doping concentration of p-type GaAs.