Tunable spin-phonon scattering in low-D spin chain compounds AB₂O₆ (A= Co, Ni; B= Sb, Ta)

We report measurements of thermal conductivity (κ) in the range 5 K ≤ T ≤ 300 K for single crystals of the low-dimensional antiferromagnetic spin-chain compounds CoSb₂O₆, NiSb₂O₆, CoTa₂O₆ and NiTa₂O₆. While all of these compounds share the same tetragonal trirutile structure with space group P4₂/mnm, Co²⁺ has a spin-3/2 and Ni²⁺ a spin-1 state. The Ta compounds show a strongly suppressed κ over a broad range of temperature relative to the Sb compounds that is typically ascribed to resonant spin-phonon scattering.^a We will discuss the possibility that this difference is caused by changes in the energy overlap of the magnon and phonon spectra associated with the B-site ion substitution.

^a A. V. Sologubenko et al., Phys. Rev. B 64, 054412 (2001).