Resonance-induced delocalization of electrons in GaAs-AlAs superlattices.
Resonance-induced delocalization of electrons in GaAs-AlAs superlattices.
复制标题
GaAs-AlAs 超晶格中共振引起的电子离域。
作者：
Schneider;Grahn;Klitzing;Ploog
本文报道了强耦合GaAs-AlAs超晶格中不同Stark阶梯之间的新型相互作用现象。我们观察到一定的激子状态之间的anticrossing行为，如果电场垂直于层的超晶格是这样的，最低的两个导子带之间的能量间隔是斯塔克阶梯间距的整数倍。这种反交叉伴随着电子状态的空间离域，因此可以通过光电流光谱来解决。我们的实验结果证实了数值计算的场依赖性的传导子带能量。
We report on novel interaction phenomena between different Stark ladders in a strongly coupled GaAs-AlAs superlattice. We observe an anticrossing behavior between certain exciton states if the electric field perpendicular to the layers of the superlattice is such that the energy spacing between the lowest two conduction subbands is an integer multiple of the Stark-ladder spacing. This anticrossing is accompanied by a spatial delocalization of the electron states and can therefore be resolved by photocurrent spectroscopy. Our experimental results are confirmed by a numerical calculation of the field dependence of the conduction-subband energies.