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arXiv · 2010.15516

Prediction of pseudogap formation due to $d$-wave bond-order in organic superconductor $\kappa$-(BEDT-TTF)$_2$X

Rina Tazai·Youichi Yamakawa·Masahisa Tsuchiizu·Hiroshi Kontani
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Abstract

Rich hidden unconventional orders with pseudogap formation, such as the inter-site bond-order (BO), attract increasing attention in condensed matter physics. Here, we investigate the hidden order formation in organic unconventional superconductor $\kappa$-(BEDT-TTF)$_2$X. We predict the formation of $d$-wave BO at wavelength $q=Q_B=(\delta,\delta)$ ($\delta=0.38\pi$) for the first time, based on both the functional renormalization group (fRG) and the density-wave equation theories. The origin of the BO is the quantum interference among antiferromagnetic spin fluctuations. This prediction leads to distinct pseudogap-like reduction in the NMR $1/T_1$ relaxation rate and in the density-of-states, consistently with essential experimental reports. The present theory would be applicable for other strongly correlated metals with pseudogap formation.

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Rina Tazai, Youichi Yamakawa, Masahisa Tsuchiizu, Hiroshi Kontani. 2020-10-29. Prediction of pseudogap formation due to $d$-wave bond-order in organic superconductor $\kappa$-(BEDT-TTF)$_2$X. https://doi.org/10.1103/physrevresearch.3.l022014

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