Phonon drag thermal Hall effect in metallic strontium titanate

Abstract

SrTiO${}_3$, a quantum paralectric, displays a detectable phonon thermal Hall effect (THE). Here we show that the amplitude of THE is extremely sensitive to stoichiometry. It drastically decreases upon substitution of a tiny fraction of Sr atoms with Ca, which stabilizes the ferroelectric order. It drastically increases by an even lower density of oxygen vacancies, which turn the system to a dilute metal. The enhancement in the metallic state exceeds by far the sum of the electronic and the phononic contributions. We explain this observation as an outcome of three features: i) heat is mostly transported by phonons; ii) the electronic Hall angle is extremely large; and iii) there is substantial momentum exchange between electrons and phonons. Starting from Herring's picture of phonon drag, we arrive to a quantitative account of the enhanced THE. Thus, phonon drag, hitherto detected as an amplifier of thermoelectric coefficients, can generate a purely thermal transverse response in a dilute metal with a large Hall angle. Our results reveal a hitherto unknown consequence of momentum-conserving collisions between electrons and phonons.ely thermal transverse response in a dilute metal with a large Hall angle. Our results reveal a hitherto unknown consequence of momentum-conserving collisions between electrons and phonons.

9 pages, six figures and a supplement

References in corpus (17)

• Robustness of the thermal Hall effect close to half-quantization in a field-induced spin liquid state
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Fermi surface of the most dilute superconductor
• Transport properties of strongly coupled electron-phonon liquids
• Electron-phonon hydrodynamics
• Charged Defects and Phonon Hall Effects in Ionic Crystals
• Quasiparticle and Nonquasiparticle Transport in Doped Quantum Paraelectrics
• Interplay between antiferrodistortive, ferroelectric and superconducting instabilities in Sr_{1-x}Ca_{x}$TiO_{3-δ}
• Isotope tuning of the superconducting dome of strontium titanate
• Extrinsic phonon thermal Hall transport from Hall viscosity
• Sizeable suppression of thermal Hall effect upon isotopic substitution in strontium titanate
• Large extrinsic phonon thermal Hall effect from resonant scattering
• Rotational $g$ factors and Lorentz forces of molecules and solids from density-functional perturbation theory
• Conductivity and thermoelectric coefficients of doped SrTiO${}_3$ at high temperatures
• Formation of an electron-phonon bi-fluid in bulk antimony
• Quasi-isotropic orbital magnetoresistance in lightly doped SrTiO${}_3$
• Optical phonon contribution to the thermal conductivity of a quantum paraelectric

Cited by in corpus (12)

• The phonon thermal Hall angle in black phosphorus
• Phonon thermal Hall effect in charge-compensated topological insulators
• T-square dependence of the electronic thermal resistivity in metallic strontium titanate
• Exchange striction induced thermal Hall effect in van der Waals antiferromagnet MnPS${}_3$
• Phonon thermal Hall effect in non-magnetic Y${}_2$Ti${}_2$O${}_7$
• Abnormally enhanced Hall Lorenz number in the magnetic Weyl semimetal NdAlSi
• Large Oscillatory Thermal Hall Effect in Kagome Metals
• Phonon thermal Hall as a lattice Aharonov-Bohm effect
• Angle-dependent planar thermal Hall effect by quasi-ballistic phonons in black phosphorus
• Soft phonon and the central peak at the cubic-to-tetragonal phase transition in SrTiO${}_3$
• Thermal Hall conductivity of semimetallic graphite dominated by ambipolar phonon drag
• Phonon Thermal Hall Effect: The Roles of Disorder, Annealing, and Metallic Contacts