Thermal conductivity of UNi0.5Sb2 single crystal

The thermal conductivity of a single crystal of UNi0.5Sb2 has been measured in the temperature range between 5 and 300 K. We find a large anisotropy in the thermal conductivity, which may be explained by the very large difference in the a and c lattice parameters. The thermal conductivity lambda(ab)(T) measured within the ab plane was found to have absolute values considerably higher than that (lambda(c)) measured along the c axis. The former exhibits at 25 K a pronounced non-symmetric maximum with an absolute value of about 6 W K-1 m(-1) and an almost symmetric minimum at T-N = 161 K. The electronic heat transport, lambda(e), was also derived from the Wiedemann-Franz law along these two crystallographic directions. Attempts to estimate the bipolar (lambda(bip)) and magnon (lambda(mag)) contents to the measured total thermal conductivity have been done. An analysis of the thermal conductivity data has been performed for both magnetically ordered and non-ordered states.