Imperfect nesting and Peierls instability for a two-dimensional tight-binding model

Qingshan Yuan; Tamara Nunner; Thilo Kopp

doi:10.1007/pl00011133

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Imperfect nesting and Peierls instability for a two-dimensional tight-binding model

Qingshan Yuan·Tamara Nunner·Thilo Kopp

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Abstract

Based on a half-filled two-dimensional tight-binding model with nearest-neighbour and next nearest-neighbour hopping the effect of imperfect Fermi surface nesting on the Peierls instability is studied at zero temperature. Two dimerization patterns corresponding to a phonon vector $(π, π)$ are considered. It is found that the Peierls instability will be suppressed with an increase of next nearest-neighbour hopping which characterizes the nesting deviation. First and second order transitions to a homogeneous state are possible. The competition between the two dimerized states is discussed.

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Qingshan Yuan, Tamara Nunner, Thilo Kopp. 2001-01-10. Imperfect nesting and Peierls instability for a two-dimensional tight-binding model. https://doi.org/10.1007/pl00011133

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