量子限制效应对限制在多量子阱中受主束缚能的影响

从实验和理论上,研究了量子限制效应对限制在GaAs/AIAs多量子阱中受主对重窄穴束缚能的影响.实验中所用的样品是通过分子束外延技术生长的一系列GaAs/AIAs多量子阱,量子阱宽度从3nm到20nm,并且在量子阱中央进行了浅受主铍(Be)原子的δ掺杂.在4,20,40,80和120K不同温度下,分别对上述系列样品进行了光致发光谱(PL)的测量,清楚地观察到了受主束缚激子从ls3/2(Г6)基态到同种宇称2s3/2(Г6)激发态的两空穴跃迁,并且从实验上测得了在不同量子阱宽度下受主的束缚能.理论上应用量子力学中的变分原理,数值计算了受主对重空穴束缚能随量子阱宽度的变化关系,比较发现理论计算和实验结果符合较好.

Effect of Quantum Confinement on Acceptor Binding Energy in Multiple Quantum Wells

We experimentally and theoretically investigate the effect of quantum confinement on the acceptor binding energy in multiple quantum wells.A series of Be delta-doped GaAs/AlAs multiple quantum wells with the doping at the well center are grown by molecular beam epitaxy.The quantum width ranges from 3 to 20nm.The photoluminescence spectra are measured at 4, 20, 40, 80, and 120K, respectively.The two-hole transitions of the acceptor-bound exciton from the ground state, 1s3/2 (Γ6) , to the even-parity excited state, 2s3/2 (Γ6) , are clearly observed and the acceptor binding energy is measured.A variational calculation is presented to obtain the acceptor binding energy as a function of well width.The experimental results agree well with the theory.