Heat conductivity of the spin-Peierls compounds TiOCl and TiOBr
arXiv:1002.2112 · doi:10.1103/PhysRevB.81.144428
Abstract
We report experimental results on the heat conductivity κof the S=1/2 spin chain compounds TiOBr and TiOCl for temperatures 5K<T<300K and magnetic fields up to 14. Surprisingly, we find no evidence of a significant magnetic contribution to κ, which is in stark contrast to recent results on S=1/2 spin chain cuprates. Despite this unexpected result, the thus predominantly phononic heat conductivity of these spin-Peierls compounds exhibits a very unusual behavior. In particular, we observe strong anomalies at the phase transitions Tc1 and Tc2. Moreover, we find an overall but anisotropic suppression of κin the intermediate phase which extends even to temperatures higher than Tc2. An external magnetic field causes a slight downshift of the transition at Tc1 and enhances the suppression of κup to Tc2. We interprete our findings in terms of strong spin-phonon coupling and phonon scattering arising from spin-driven lattice distortions.
arXiv comment6 pages, 3 figures
References in corpus (31)
- Transport and conservation laws
- Magnon Heat Transport in (Sr,La)_14Cu_24O_41
- Heat transport by lattice and spin excitations in the spin chain compounds SrCuO_2 and Sr_2CuO_3
- Zero-frequency transport properties of one dimensional spin-1/2 systems
- The thermal conductivity of the spin-1/2 XXZ chain at arbitrary temperature
- S=1/2 chains and spin-Peierls transition in TiOCl
- Heat conduction in low-dimensional quantum magnets
- Ballistic heat transport of quantum spin excitations as seen in SrCuO2
- Spin-Peierls transition in TiOCl
- Reexamination of the microscopic couplings of the quasi one-dimensional antiferromagnet CuGeO_3
- Thermal Conductivity of the Spin Peierls Compound CuGeO_3
- Zero-field incommensurate spin-Peierls phase with interchain frustration in TiOCl
- Orbital order in the low-dimensional quantum spin system TiOCl probed by ESR
- Magnon-Hole Scattering and Charge Order in
- Magnetic heat conductivity in : linear temperature dependence
- Anomalous expansion and phonon damping due to the Co spin-state transition in RCoO_3 with R = La, Pr, Nd and Eu
- Incommensurate interactions and non-conventional spin-Peierls transition in TiOBr
- Two pressure-induced transitions in TiOCl: Mott insulator to anisotropic metal
- Heat capacity of the quantum magnet TiOCl
- Universal behavior of spin-mediated energy transport in S=1/2 chain cuprates: BaCu2Si2O7 as an example
- Unusual quasi-one-dimensional electron dispersions in the spin-1/2 quantum magnet TiOCl
- X-ray Scattering Study of the spin-Peierls transition and soft phonon behavior in TiOCl
- Magnon Heat Conductivity and Mean Free Paths in Two-Leg Spin Ladders: A Model-Independent Determination
- Phonon thermal conductivity in doped : Relevant scattering mechanisms
- Muon-spin relaxation measurements on the dimerized spin-1/2 chains NaTiSi2O6 and TiOCl
- Symmetry disquisition on the TiOX phase diagram
- Thermal conductivity of doped as an example for heat transport by optical phonons in complex materials
- Heat transport in SrCu_2(BO_3)_2 and CuGeO_3
- Commensurate Fluctuations in the Pseudogap and Incommensurate spin-Peierls Phases of TiOCl
- Critical properties of the unconventional spin-Peierls system TiOBr
- Microscopic theory for the incommensurate transition in TiOCl