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DECOHERENCE OF THE TRIANGULAR BOUND POTENTIAL QUANTUM DOT QUBIT

JIA-KUI SUN

College of Physics and Electronic Information, Inner Mongolian University for Nationalities, Tongliao 028043, China

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HONG-JUAN LI

College of Physics and Electronic Information, Inner Mongolian University for Nationalities, Tongliao 028043, China

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, and

JING-LIN XIAO

College of Physics and Electronic Information, Inner Mongolian University for Nationalities, Tongliao 028043, China

Corresponding author.

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https://doi.org/10.1142/S0217984909021296Cited by:7 (Source: Crossref)

Abstract

We study the eigenenergies and the eigenfunctions of the ground and the first excited states of an electron, which is strongly coupled to the LO-phonon in a quantum dot with triangular bound potential by using the Pekar variational method. This system may be used as a two-level qubit. Our numerical results indicate that the decoherence rate will decrease with increasing the confinement length of the quantum dot (QD) and decrease with increasing electron-LO-phonon coupling constant. The influences of the polar angle on the decoherence rate are dominant when the coupling constant increases, while the effects of the polar angle on that are strong when the confinement length increases. Meanwhile, the decoherence rate varies periodically with respect to the polar angle.

Keywords:

PACS: 73.21.La, 03.65.Yz, 03.67.Lx

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