Thermal conductivity of USb₂ and UBi₂ single crystals

Abstract

The thermal conductivity (κ) of single crystals of tetragonal uniaxial antiferromagnets USb₂ (T _N = 202 K) and UBi₂ (T _N = 180.8 K) has been measured along the a-axis (κ_a ) over the temperature range from 0.5 to 300 K and along the c-axis (κ_c ) from 0.5 to 70 K. The as-grown samples have residual resistivity ratio (RRR) values of about 500–600 and 100–150 for UBi₂ and USb₂, respectively. The anisotropy of the thermal conductivity (κ_a (T)/κ_c (T) ∼ 5) and the low-T Lorenz ratios are discussed in relation to Fermi surface topology for both compounds.

Keywords:

• uranium dipnictides
• thermal conductivity
• anisotropy

Acknowledgement

The authors are indebted to Dr. R.E. Baumbach for his assistance with manuscript editing.