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arXiv · 1212.1868

Electron-electron correlations in a dynamical impurity system with a Fermi edge singularity

I. Snyman
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Abstract

We study spatial correlations in the ground state of a one-dimensional electron gas coupled to a dynamic quantum impurity. The system displays a non-trivial many-body effect known as the Fermi edge singularity: transitions between discrete internal states of the impurity have a power-law dependence on the internal energies of the impurity states. We present compact formulas for the static current-current correlator and the pair correlation function. These reveal that spatial correlations induced by the impurity decay slowly (as the third inverse power of distance) and have a power-law energy dependence, characteristic of the Fermi edge singularity.

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I. Snyman. 2012-12-09. Electron-electron correlations in a dynamical impurity system with a Fermi edge singularity. https://doi.org/10.1103/physrevb.87.165135

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