Extremely low temperature coefficient of resistivity in antiperovskite compounds MσGa1−σCFe3 (M = Cu, Ag)

Abstract

We report the effects of substitution of Cu/Ag/Zn/Sn for Ga on the temperature coefficient of resistivity (TCR) of antiperovskite GaCFe3. With both Cu and Ag dopants increasing, the resistivity displays a peak over a broad temperature range (or low TCR value) around room temperature. As a result, the Cu/Ag dopant can sufficiently optimize the TCR value. For Ag0.05Ga0.95CFe3, the averaged TCR values are less than 10.74ppm/K (215–350K) and, especially, as low as 2.51ppm/K (260–300K). Similarly, the averaged TCR values are 28.87ppm/K (220–273K) in Cu0.05Ga0.95CFe3 and 19.20ppm/K (235–287K) in Cu0.1Ga0.9CFe3. Considering the extremely low averaged TCR value, broad temperature range around room temperature, friendly to the environment, and good thermostability, the series of CuxGa1−xCFe3 and AgxGa1−x CFe3 can be promising low TCR materials.