Quantum device with plural stable states

摘要

A quantum box array comprising a plurality of quantum boxes is made by providing a plurality of box-shaped quantum well portions on a first barrier layer and a second barrier layer covering the quantum well portions. The quantum box array is designed so that interaction energy between electrons or holes is amply larger than transfer energy between the quantum boxes. A control electrode is provided on the second barrier layer to vary the number of electrons or holes in the quantum box array by changing the potential of the control electrode. In spite of using a relatively small number of electrons or holes, the quantum device can suppress fluctuation in density of electrons or holes, can have three or more states, and reduces the power consumption.