Instability toward Formation of Quasi-One-Dimensional Fermi Surface in Two-Dimensional t-J Model

Hiroyuki Yamase; Hiroshi Kohno

doi:10.1143/jpsj.69.2151

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arXiv · 2104.10467

Instability toward Formation of Quasi-One-Dimensional Fermi Surface in Two-Dimensional t-J Model

Hiroyuki Yamase·Hiroshi Kohno

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Abstract

We show within the slave-boson mean field approximation that the two-dimensional t-J model has an intrinsic instability toward forming a quasi-one-dimensional (q-1d) Fermi surface. This q-1d state competes with, and is overcome by, the d-wave pairing state for a realistic parameter choice. However, we find that a small spatial anisotropy in t and J exposes the q-1d instability which has been hidden behind the d-wave pairing state, and brings about the coexistence with the d-wave pairing. We argue that this coexistence can be realized in La_{2-x}Sr_{x}CuO_4 systems

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Hiroyuki Yamase, Hiroshi Kohno. 2021-04-21. Instability toward Formation of Quasi-One-Dimensional Fermi Surface in Two-Dimensional t-J Model. https://doi.org/10.1143/jpsj.69.2151

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