$d$-wave Superconductivity in the Hubbard model on the isotropic triangular lattice and a possibility of the chiral $d+id$ pairing as a quasi-stable state

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Yamada, A.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909548494716928
author Yamada, A.
author_facet Yamada, A.
contents We study $d$-wave superconductivity(SC) in the Hubbard model on the isotropic triangular lattice described by the hopping parameter $t$ and on-site Coulomb repulsion $U$ at zero temperature and half-filling using the variational cluster approximation. We found that the $d_{xy}$ SC is the ground state below the Mott insulator phase $U/t \lesssim 6$, and the energy of chiral $d+id$ SC is slightly higher than the $d_{xy}$ SC. The energy difference between the normal and $d_{xy}$ states is about $0.02t \sim 0.06t$ for $U/t \simeq 5$. This result is semi-quantitatively consistent with the SC transition temperature $T_K=3.9$ K of $κ$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$, where $t$ is estimated to be about $0.06$ eV, and the predicted pairing symmetry $d_{xy}$ agrees with the STM observations. The energy difference between the $d+id$ and $d_{xy}$ is about $0.01t\sim 0.03t$ for $U/t \simeq 5$ so the transition from $d+id$ to $d_{xy}$, or some effects of $d+id$ in $d_{xy}$ phase may be observed in experiments for $κ$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$.
format Preprint
id arxiv_https___arxiv_org_abs_2409_19832
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle $d$-wave Superconductivity in the Hubbard model on the isotropic triangular lattice and a possibility of the chiral $d+id$ pairing as a quasi-stable state
Yamada, A.
Strongly Correlated Electrons
We study $d$-wave superconductivity(SC) in the Hubbard model on the isotropic triangular lattice described by the hopping parameter $t$ and on-site Coulomb repulsion $U$ at zero temperature and half-filling using the variational cluster approximation. We found that the $d_{xy}$ SC is the ground state below the Mott insulator phase $U/t \lesssim 6$, and the energy of chiral $d+id$ SC is slightly higher than the $d_{xy}$ SC. The energy difference between the normal and $d_{xy}$ states is about $0.02t \sim 0.06t$ for $U/t \simeq 5$. This result is semi-quantitatively consistent with the SC transition temperature $T_K=3.9$ K of $κ$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$, where $t$ is estimated to be about $0.06$ eV, and the predicted pairing symmetry $d_{xy}$ agrees with the STM observations. The energy difference between the $d+id$ and $d_{xy}$ is about $0.01t\sim 0.03t$ for $U/t \simeq 5$ so the transition from $d+id$ to $d_{xy}$, or some effects of $d+id$ in $d_{xy}$ phase may be observed in experiments for $κ$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$.
title $d$-wave Superconductivity in the Hubbard model on the isotropic triangular lattice and a possibility of the chiral $d+id$ pairing as a quasi-stable state
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2409.19832