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arXiv · 0802.1229

Rate of decoherence for an electron weakly coupled to a phonon gas

Riccardo Adami·Laszlo Erdos
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Abstract

We study the dynamics of an electron weakly coupled to a phonon gas. The initial state of the electron is the superposition of two spatially localized distant bumps moving towards each other, and the phonons are in a thermal state. We investigate the dynamics of the system in the kinetic regime and show that the time evolution makes the non-diagonal terms of the density matrix of the electron decay, destroying the interference between the two bumps. We show that such a damping effect is exponential in time, and the related decay rate is proportional to the total scattering cross section of the electron-phonon interaction.

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Riccardo Adami, Laszlo Erdos. 2008-02-08. Rate of decoherence for an electron weakly coupled to a phonon gas. https://doi.org/10.1007/s10955-008-9561-8

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