Near-Zero Temperature Coefficient Of Resistivity In Lafe9.45al3.55 Compound Over 5-300k

The temperature coefficient of resistivity (TCR) was systematically investigated in La (Fe, Al)(13) compounds with an Al atomic content from 3.40 to 3.70. We find that the local extremum of the TCR is obtained in LaFe9.45Al3.55, which is -20.914ppm/K over 5-300K. It is rare for TCR to stay at such a low level over such a wide temperature range below 300K. Our work revealed that all compounds remain the same structure of cubic NaZn13-type (space group: Fm3c) based on synchrotron radiation X-ray diffraction (SR-XRD) and X-ray powder diffraction (XRD) tests. The magnetization-temperature curves indicate that all samples are ferromagnet. We analyzed the effect of structure on the performance from the perspective of the Fe-Fe atomic distance. These peculiar behaviors are possibly due to the competitive effect by magnetic scattering and e-p scattering.