【摘要】 我们研究了掺杂耦合ＧａＡｓ／ＡｌＡｓ超晶格的级联隧穿，在这种结构中，ＡｌＡｓ层Ｘ能谷中的基态能级位于ＧａＡｓ层中Γ能谷的基态（Ｅ（Γ１）；）和第一激发态（Ｅ（Γ２））能级之间．实验结果证明，这种超晶格中的高电场畴是由Γ－Ｘ级联共振隧穿所形成的，而不是通常的相邻量子阱子带的级联共振隧穿所形成的．在这种高场畴中，电子从ＧａＡｓ量子阱的基态隧穿到邻近的ＡｌＡｓ层的Ｘ能谷的基态，然后通过实空间电子转移从ＡｌＡｓ层的Ｘ能谷弛豫到下一个ＧａＡｓ量子阱的Γ能谷的基态．更多还原

【Abstract】 Abstract We have studied the sequential tunneling of doped weakly-coupled GaAs/AlAs superlattices (SLs), whose ground state of X valley in AlAs layers is designed to be located between the ground state (E) and the first excited state (E) of valley in GaAs wells.The experimental results demonstrate that the high electric field domain in these SLs is attributed to the X sequential tunneling instead of the usual sequential resonant tunneling between subbands in adjacent wells. Within this kind of high field domain, electrons from the ground state in GaAs well tunnel to the ground state of X valley in the nearest AlAs layer, then through very rapid real-space transfer from the X valley in the AlAs layer relax to the ground state of valley of the next GaAs well.更多还原