High thermal conductivity of solid nitrous oxide at low temperatures

Abstract

Thermal conductivity of crystalline nitrous oxide was investigated over the temperature range 1.2--40 K. Temperature dependence of the thermal conductivity has been determined at temperatures below 23 K. Thermal conductivity coefficient exhibits a surprisingly---compared with simple molecular crystals such as ${\mathrm{N}}_{2},$ CO, or ${\mathrm{O}}_{2}$---high value in the whole investigated temperature range. Both the experimental results themselves and the method of Callaway applied to the experimental data analysis indicate that relatively low density of dislocations and weak phonon-phonon interaction might be reasons for the good thermal conduction in solid ${\mathrm{N}}_{2}\mathrm{O}.$ The problem of influence of possible low-temperature dipolar ordering on thermal conductivity of nitrous oxide crystal is speculated.