Cuprate Superconductors in the Vicinity of a Pomeranchuk Instability

Hiroyuki Yamase

doi:10.1016/j.jpcs.2008.06.073

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arXiv · 2108.01935

Cuprate Superconductors in the Vicinity of a Pomeranchuk Instability

Hiroyuki Yamase

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Abstract

We propose that cuprate superconductors are in the vicinity of a spontaneous d-wave type Fermi surface symmetry breaking, often called a d-wave Pomeranchuk instability. This idea is explored by means of a comprehensive study of magnetic excitations within the slave-boson mean-field theory of the t-J model. We can naturally understand the pronounced xy anisotropy of magnetic excitations in untwinned YBa_{2}Cu_{3}O_{y} and the sizable change of incommensurability of magnetic excitations at the transition temperature to the low-temperature tetragonal lattice structure in La_{2-x}Ba_{x}CuO_{4}. In addition, the present theoretical framework allows the understanding of the similarities and differences of magnetic excitations in Y-based and La-based cuprates.

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Hiroyuki Yamase. 2021-08-04. Cuprate Superconductors in the Vicinity of a Pomeranchuk Instability. https://doi.org/10.1016/j.jpcs.2008.06.073

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