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arXiv · 1011.3881

Lifshitz transition in two-dimensional spin-density wave models

Jie Lin
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Abstract

We argue that both pocket-disappearing and neck-disrupting types of Lifshitz transitions can be realized in two-dimensional spin-density wave models for underdoped cuprates, and study both types of transitions with impurity scattering treated in the self-consistent Born approximation. We first solve for the electron self-energy from the self-consistent equation, and then study the low-temperature electrical conductivity and thermopower. Close to the Lifshitz transition, the thermopower is strongly enhanced. For the pocket-disappearing type, it has a sharp peak, while for the neck-disrupting type, it changes sign at the transition, with its absolute value peaked on both sides of the transition. We discuss possible applications to underdoped cuprates.

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Jie Lin. 2010-11-17. Lifshitz transition in two-dimensional spin-density wave models. https://doi.org/10.1103/physrevb.82.195110

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