Q=0 collective modes originating from the low-lying Hg-O band in the superconducting HgBa2CuO4+δ

Abstract

Motivated by the recent discovery of two Q\sim0 collective modes [Y. Li et al., Nature 468, 283 (2010); ibid Nat. Phys. 8, 404 (2012)] in the single-layer HgBa2CuO4+δ, which are often taken as evidence of the orbital current origin of a pseudogap, we examine an alternative and assumption-free scenario constrained by first-principle calculations. We find that in addition to the common CuO2 band, a hybridized Hg-O state is present in the vicinity of the Fermi level, and that it contributes to the low-energy ground state of this system. We calculate the spin-excitation spectrum based on the random-phase-approximation in the superconducting state using a two band model and show that a collective mode in the multi-orbital channel arises at Q=0. This mode splits in energy, yet remains at Q\sim0 as the pseudogap develops breaking both translational and time-reversal symmetries in the spin-channel, and thus gap out the electrnic states. The observations of the dynamical mode and static moment in the pseudogap state are in good accord with experimental observations. A verifiable prediction of this proposal is the development of magnetic order also in the Hg-O layer. Detection of Hg-O band via optical study, or magnetic moment in the Hg-O layer will be tests of this calculation.

5 pages, 4 figures. (v2): published version, slightly revisions in couple of places

References in corpus (8)

• Quantum oscillations and the Fermi surface in an underdoped high-Tc superconductor
• Electronic liquid crystal state in the high-temperature superconductor YBCO(6.45)
• Magnetic order in the pseudogap phase of high-$T_C$ superconductors
• Electron pockets in the Fermi surface of hole-doped high-Tc superconductors
• Quantum Oscillations in the Underdoped Cuprate YBa2Cu4O8
• Testing the itinerancy of spin dynamics in superconducting Bi2212
• A competing order scenario of two-gap behavior in hole doped cuprates
• Two Ising-like magnetic excitations in a single-layer cuprate superconductor

Cited by in corpus (8)

• Intermediate Coupling Model of the Cuprates
• SU(2)-symmetry in a realistic spin-fermion model for cuprate superconductors
• Three interaction energy scales in single-layer high-T${}_C$ cuprate HgBa${}_2$CuO${}_{4+\delta }$
• Transport properties and doping evolution of the Fermi surface in cuprates
• Observation of the Yamaji effect in a cuprate superconductor
• First-principles electronic structure investigation of HgBa${}_2$Ca${}_{n-1}$Cu${}_n$O${}_{2n+2+x}$ with the SCAN density functional
• Discerning electronic fingerprints of nodal and antinodal nestings and their phase coherences in doped cuprate superconductors
• Aspects of the normal state resistivity of cuprate superconductors Bi2201, Tl2201 and Hg1201