Anomalous thermal conductivity of single crystal Cu2Te2O5Cl2

Abstract

A strong increase of the thermal conductivity is observed at the phase transition (T c =18.2 K) in Cu 2 Te 2 O 5 Cl 2 single crystal. This behavior is compared with that of spinPeierls system NaV 2 O 5 , where similar experimental observation has been found, and the conventional spin-Peierls system CuGeO 3, where a modest kink in the thermal conductivity curve has been observed. The strong increase of the thermal conductivity at T c in Cu 2 Te 2 O 5 Cl 2 could be partially attributed to the opening of the energy gap in the magnetic excitation spectrum evident from the magnetic susceptibility measurements. However, the main reason for the anomaly of the thermal conductivity could be explained by a strong spin-lattice coupling in this system, while in NaV 2 O 5 it is a consequence of a charge ordering.2

AC measurement of heat capacity and magnetocaloric effect for pulsed magnetic fields

“…We chose a 30 m thickness and 0.1 W K −1 m −1 thermal conductivity for the contact layer ͑silver paint͒. 36 Other physical values used in this calculation, such as heat capacity and thermal conductivity in each region, are taken from the literature; [36][37][38][39][40][41][42][43][44][45][46][47][48] these values are listed in the figure caption of Fig. 7.…”

Magnetic, electrical and thermal transport properties of Al–Cr–Fe approximant phases

“…The thermal flux through the samples was generated by a 1 k RuO 2 chip-resistor, glued to one end of the sample, while the other end was attached to a copper heat sink. The temperature gradient across the sample was monitored by a chromel-constantan differential thermocouple (more detailed description can be found elsewhere [19]). The temperature dependence of the thermal conductivity parameter κ(T) of both samples is displayed in Fig.…”