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

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.

8 pages, 7 figures, Figure 4 (e) has been added, to be published in Phys. Rev. Research

References in corpus (18)

• Unfolding first-principles band structures
• Striped superconductors: How the cuprates intertwine spin, charge and superconducting orders
• Quantum frustration in organic Mott insulators: from spin liquids to unconventional superconductors
• Unconventional critical behaviour in a quasi-two-dimensional organic conductor
• Incipient charge order observed by NMR in the normal state of YBa2Cu3Oy
• Direct phase-sensitive identification of a d-form factor density wave in underdoped cuprates
• Thermodynamic evidence for nematic phase transition at the onset of pseudogap in YBa${}_2$Cu${}_3$O${}_y$
• Mott Transition, Antiferromagnetism, and d-wave Superconductivity in Two-Dimensional Organic Conductors
• Self-Consistent Vertex Correction Analysis for Iron-Based Superconductors: Mechanism of Coulomb-Interaction-Driven Orbital Fluctuations
• Anomalous Transport Phenomena in Fermi Liquids with Strong Magnetic Fluctuations
• Visualizing the emergence of the pseudogap state and the evolution to superconductivity in a lightly hole-doped Mott insulator
• Instabilities near the onset of spin density wave order in metals
• Incommensurate nematic fluctuations in the two-dimensional Hubbard model
• Charge instabilities at the metamagnetic transition
• Staggered Flux State in Two-Dimensional Hubbard Models
• Microscopic observation of superconducting fluctuations in $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br by ${}^{13}$C NMR spectroscopy
• Microscopic evidence for the intra-unit-cell electronic nematicity inside the pseudogap phase in YBa${}_2$Cu${}_4$O${}_8$
• Possible observation of the signature of the bad metal phase and its crossover to a Fermi liquid in K(BEDT-TTF)2Cu(NCS)2 bulk and nanoparticles by Raman scattering

Cited by in corpus (4)

• Unconventional density waves and superconductivities in Fe-based superconductors and other strongly correlated electron systems
• Generation of odd-frequency surface superconductivity with spontaneous spin current due to the zero-energy Andreev bound state
• Unconventional orbital-charge density wave mechanism in transition metal dichalcogenide 1T-TaS2
• Odd-parity quadrupole order and induced nonreciprocal transport in the kagome metal CsTi${}_3$Bi${}_5$ driven by quantum interference