Thermal Hall conductivity of electron-doped cuprates

Abstract

Measurements of the thermal Hall conductivity in hole-doped cuprates have shown that phonons acquire chirality in a magnetic field, both in the pseudogap phase and in the Mott insulator state. The microscopic mechanism at play is still unclear. A number of theoretical proposals are being considered, including skew scattering of phonons by various defects, the coupling of phonons to spins, and a state of loop-current order with the appropriate symmetries, but more experimental information is required to constrain theoretical scenarios. Here we present our study of the thermal Hall conductivity ${\kappa }_{\mathrm{xy}}$ in the electron-doped cuprates Nd${}_{2-x}$Ce${}_x$CuO${}_4$ and Pr${}_{2-x}$Ce${}_x$CuO${}_4$, for dopings across the phase diagram, from $x$ = 0, in the insulating antiferromagnetic phase, up to $x$ = 0.17, in the metallic phase above optimal doping. We observe a large negative thermal Hall conductivity at all dopings, in both materials. Since heat conduction perpendicular to the CuO${}_2$ planes is dominated by phonons, the large thermal Hall conductivity we observe in electron-doped cuprates for a heat current in that direction must also be due to phonons, as in hole-doped cuprates. Measurements with a heat current perpendicular to the CuO${}_2$ planes confirm that phonons are responsible for this thermal Hall signal, as in hole-doped cuprates. However, the degree of chirality, measured as the ratio $|{\kappa }_{\mathrm{xy}}$ / ${\kappa }_{\mathrm{xx}}|$, where ${\kappa }_{\mathrm{xx}}$ is the longitudinal thermal conductivity, is much larger in the electron-doped cuprates. We discuss various factors that may be involved in the mechanism that confers chirality to phonons in cuprates, including short-range spin correlations.

10 pages, 9 figures

References in corpus (12)

• Observation of the Magnon Hall Effect
• Spin correlations in the electron-doped high-transition-temperature superconductor Nd{2-x}Ce{x}CuO{4+/-delta}
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Phonons become chiral in the pseudogap phase of cuprates
• Finite doping signatures of the Mott transition in the two-dimensional Hubbard model
• Microscopic annealing process and its impact on superconductivity in T'-structure electron-doped copper oxides
• Thermal Hall conductivity in the cuprate Mott insulators Nd${}_2$CuO${}_4$ and Sr${}_2$CuO${}_2$Cl${}_2$
• Origin of the Phonon Hall Effect in Rare-Earth Garnets
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• Extrinsic phonon thermal Hall transport from Hall viscosity
• Thermal Hall effect in the pseudogap phase of cuprates
• Phonon Hall Viscosity in Magnetic Insulators

Cited by in corpus (13)

• Thermal Hall effects in quantum magnets
• Large Phonon Thermal Hall Conductivity in a Simple Antiferromagnetic Insulator
• Resonant thermal Hall effect of phonons coupled to dynamical defects
• Impurity-induced phonon thermal Hall effect in the antiferromagnetic phase of Sr2IrO4
• Phonon thermal Hall effect in charge-compensated topological insulators
• Chiral spin liquid and quantum phase diagram of spin-$1/2$ $J_1$-$J_2$-$J_{\chi }$ model on the square lattice
• Phonon thermal Hall effect in non-magnetic Y${}_2$Ti${}_2$O${}_7$
• Planar thermal Hall effect from phonons in cuprates
• Disorder effects on hot spots in electron-doped cuprates
• Role of magnetic ions in the thermal Hall effect of the paramagnetic insulator TmVO${}_4$
• Chiral phonons in binary compounds $A$Bi ($A$ = K, Rb, Cs) with P2${}_1$/c structure
• Phonon Thermal Hall Effect in a non-Kramers Paramagnet
• Thermal Hall conductivity in the strongest cuprate superconductor: Estimate of the mean free path in the trilayer cuprate HgBa${}_2$Ca${}_2$Cu${}_3$O${}_{8+\delta }$