Sizeable suppression of thermal Hall effect upon isotopic substitution in strontium titanate

Abstract

We report measurements of the thermal Hall effect in single crystals of both pristine and isotopically substituted strontium titanate. We discovered a two orders of magnitude difference in the thermal Hall conductivity between $SrT{i}^{16}{O}_3$ and ${}^{18}O$-enriched $SrT{i}^{18}{O}_3$ samples. In most temperature ranges, the magnitude of thermal Hall conductivity (${\kappa }_{xy}$) in $SrT{i}^{18}{O}_3$ is proportional to the magnitude of the longitudinal thermal conductivity (${\kappa }_{xx}$), which suggests a phonon-mediated thermal Hall effect. However, they deviate in the temperature of their maxima, and the thermal Hall angle ratio ($|{\kappa }_{xy}/{\kappa }_{xx}|$) shows anomalously decreasing behavior below the ferroelectric Curie temperature $T_c$ ~$25K$. This observation suggests a new underlying mechanism, as the conventional scenario cannot explain such differences within the slight change in phonon spectrum. Notably, the difference in magnitude of thermal Hall conductivity and rapidly decreasing thermal Hall angle ratio in $SrT{i}^{18}{O}_3$ is correlated with the strength of quantum critical fluctuations in this displacive ferroelectric. This relation points to a link between the quantum critical physics of strontium titanate and its thermal Hall effect, a possible clue to explain this example of an exotic phenomenon in non-magnetic insulating systems.

arXiv comment11 pages, 4 figures, accepted for publication in Physical Review Letters

References in corpus (23)

• Majorana quantization and half-integer thermal quantum Hall effect in a Kitaev spin liquid
• Observation of the Magnon Hall Effect
• Theory of Thermal Hall Effect in Quantum Magnets
• Quantum criticality in ferroelectrics
• The thermal Hall effect of spin excitations in a Kagome magnet
• Unusual thermal Hall effect in a Kitaev spin liquid candidate $\alpha$-RuCl${}_3$
• Thermal Hall conductivity in the frustrated pyrochlore magnet Tb2Ti2O7
• Giant thermal Hall conductivity from neutral excitations in the pseudogap phase of cuprates
• Phonons become chiral in the pseudogap phase of cuprates
• Theory of Phonon Hall Effect in Paramagnetic Dielectrics
• Thermal transport and phonon hydrodynamics in strontium titanate
• Phonon thermal Hall effect in strontium titanate
• Superconductivity at very low density: the case of strontium titanate
• Thermal Hall Effect of Spins in a Paramagnet
• Thermal Hall effect in a phonon-glass Ba${}_3$CuSb${}_2$O${}_9$
• Thermal Hall conductivity in the cuprate Mott insulators Nd${}_2$CuO${}_4$ and Sr${}_2$CuO${}_2$Cl${}_2$
• Enhanced thermal Hall effect in nearly ferroelectric insulators
• Origin of the Phonon Hall Effect in Rare-Earth Garnets
• Berry phase of phonons and thermal Hall effect in nonmagnetic insulators
• Chirality-driven Hall Transport Phenomena of Spins
• Topological magnons with nodal-line and triple-point degeneracies: Implications for thermal Hall effect in pyrochlore iridates
• Quantum Critical Phenomena in a Compressible Displacive Ferroelectric
• Phonon Hall effect in ionic crystals in the presence of static magnetic field

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