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arXiv · 0711.4882

Transmission phase shift of phonon-assisted tunneling through a quantum dot

Juntao Song·Qing-feng Sun·Hua Jiang·X. C. Xie
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Abstract

The influence of electron-phonon interaction on the transmission phase shift of an electron passing through a quantum dot is investigated by using the scattering theory. The transmission phase versus the intra-dot level shows a serial of phonon-induced dips. These dips are highly sensitive to electron-phonon interaction strength $λ$, and they are much more pronounced than phonon-assisted sub-peaks appeared in the conductance. Phonon-induce dephasing is also studied, and the results show that the dephasing probability $T_d$ monotonically increases with the electron-phonon interaction strength $λ$. The dephasing probability $T_d \proptoλ^2$ for small $λ$ but $T_d\propto λ$ at large $λ$.

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Juntao Song, Qing-feng Sun, Hua Jiang, X. C. Xie. 2007-11-30. Transmission phase shift of phonon-assisted tunneling through a quantum dot. https://doi.org/10.1103/physrevb.77.035309

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