Low-temperature specific heat and heat transport of Tb${}_2$Ti${}_{2-x}$Zr${}_x$O${}_7$ single crystals

Abstract

We report a study on the specific heat and heat transport of Tb${}_2$Ti${}_{2-x}$Zr${}_x$O${}_7$ ($x=$ 0, 0.02, 0.1, 0.2, and 0.4) single crystals at low temperatures and in high magnetic fields. The magnetic specific heat can be described by the Schottky contribution from the crystal-electric-field (CEF) levels of Tb${}^{3+}$, with introducing Gaussian distributions of the energy split of the ground-state doublet and the gap between the ground state and first excited level. These crystals has an extremely low phonon thermal conductivity in a broad temperature range that can be attributed to the scattering by the magnetic excitations, which are mainly associated with the CEF levels. There is strong magnetic field dependence of thermal conductivity, which is more likely related to the field-induced changes of phonon scattering by the CEF levels than magnetic transitions or spin excitations. For magnetic field along the [111] direction, there is large thermal Hall conductivity at low temperatures which displays a broad peak around 8 T. At high fields up to 14 T, the thermal Hall conductivity decreases to zero, which supports its origin from either the spinon transport or the phonon skew scattering by CEF levels. The thermal Hall effect is rather robust with Zr doping up to 0.2 but is strongly weakened in higher Zr-doped sample.

9 pages, 8 figures, accepted for publication in Phys. Rev. B

References in corpus (19)

• Observation of the Magnon Hall Effect
• Half-integer quantized anomalous thermal Hall effect in the Kitaev material $\alpha$-RuCl${}_3$
• Dynamically-Induced Frustration as a Route to a Quantum Spin Ice State in Tb2Ti2O7 via Virtual Crystal Field Excitations and Quantum Many-Body Effects
• Disordered Route to the Coulomb Quantum Spin Liquid: Random Transverse Fields on Spin Ice in Pr${}_2$Zr${}_2$O${}_7$
• Emergence of nontrivial magnetic excitations in a spin liquid state of kagome volborthite
• Magnetic phase transitions and magnetoelectric coupling of GdFeO_3 single crystals probed by low-temperature heat transport
• Ground state and magnetic phase transitions of orthoferrite DyFeO_3
• Field Induced Order and Spin Waves in the Pyrochlore Antiferromagnet Tb2Ti2O7
• Origin of the Phonon Hall Effect in Rare-Earth Garnets
• Large magnetothermal conductivity of HoMnO_3 single crystals and its relation to the magnetic-field induced transitions of magnetic structure
• Survival of itinerant excitations and quantum spin state transitions in YbMgGaO${}_4$ with chemical disorder
• Low-Temperature Heat Transport in the Low-Dimensional Quantum Magnet NiCl_{2}-4SC(NH_{2})_{2}
• Field induced spin ice like orders in spin liquid Tb${}_2$Ti${}_2$O${}_7$
• Magnetic order and single-ion anisotropy in Tb${}_3$Ga${}_5$O${}_{12}$
• Low-temperature transport properties of intermetallic compound HoAgGe with kagome spin ice state
• Low-temperature heat transport and magnetic-structure transition of the hexagonal TmMnO_3 single crystals
• Thermal conductivity of IPA-CuCl_3: Evidences of ballistic magnon transport and limited applicability of the Bose-Einstein condensation model
• Low Energy Magneto-optics of Tb${}_2$Ti${}_2$O${}_7$ in [111] Magnetic Field
• Elastic study of electric quadrupolar correlation in the paramagnetic state of a frustrated quantum magnet $\mathrm{T}{\mathrm{b}}_{2+\delta }\mathrm{T}{\mathrm{i}}_{2-\delta }{\mathrm{O}}_7$

Cited by in corpus (1)

• Thermal Hall effects in quantum magnets