Acta Physica Sinica

Two-electron InAs quantum-dot-molecular qubit modulated by the orientation of magnetic fields

Dong Qing-Rui, 山东师范大学物理与电子科学学院，济南 250014

Published Jan 1, 2007• 1 citation

Abstract

The electronic structure of a two-electron quantum-dot molecular has studied using the effective mass approximation. The quantum-dot molecular consists of two vertically coupled self-assembled quantum disks in a magnetic field with varying orientation. Based on the calculation, a qubit modulated by the orientation of magnetic field is proposed with the total spin of the system. Electron correlations may lead to the switching of the total spin between S=0 and S=1 states. The switching is realized not by the changing strength but by the changing orientation of an external magnetic field. Our results provide a possibility to use the total spin of the system as a qubit modulated by varying the orientation of the magnetic field. Since high-quality vertically stacked quantum disks can be fabricated successfully, it is realistic to obtain qubits of this type.

DOI: 10.7498/aps.56.5436

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