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Gate control of spin dynamics in III-V semiconductor quantum dots

Rogerio de Sousa·S. Das Sarma
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Abstract

We show that the g-factor and the spin-flip time T_{1} of a heterojunction quantum dot is very sensitive to the band-bending interface electric field even in the absence of wave function penetration into the barrier. When this electric field is of the order of 10^{5} V/cm, g and T_{1} show high sensitivity to dot radius and magnetic field arising from the interplay between Rashba and Dresselhaus spin-orbit interactions. This result opens new possibilities for the design of a quantum dot spin quantum computer where g-factor and T_{1} can be engineered by manipulating the spin-orbit coupling through external gates.

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Rogerio de Sousa, S. Das Sarma. 2003-09-30. Gate control of spin dynamics in III-V semiconductor quantum dots. https://doi.org/10.1103/physrevb.68.155330

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