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arXiv · 1607.05725

Non-quasiparticle transport and resistivity saturation: A view from the large-N limit

Yochai Werman·Steven A. Kivelson·Erez Berg
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Abstract

The electron dynamics in metals are usually well described by the semiclassical approximation for long-lived quasiparticles. However, in some metals, the scattering rate of the electrons at elevated temperatures becomes comparable to the Fermi energy; then, this approximation breaks down, and the full quantum-mechanical nature of the electrons must be considered. In this work, we study a solvable, large-$N$ electron-phonon model, which at high temperatures enters the non-quasiparticle regime. In this regime, the model exhibits "resistivity saturation" to a temperature-independent value of the order of the quantum of resistivity - the first analytically tractable model to do so. The saturation is not due to a fundamental limit on the electron lifetime, but rather to the appearance of a second conductivity channel. This is suggestive of the phenomenological "parallel resistor formula", known to describe the resistivity of a variety of saturating metals.

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Yochai Werman, Steven A. Kivelson, Erez Berg. 2016-07-19. Non-quasiparticle transport and resistivity saturation: A view from the large-N limit. https://doi.org/10.1038/s41535-017-0009-8

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