UC Irvine

We present measurements of the linear expansion coefficient, α, on Fe1-xCoxSi from 40 to 300 K and for x = 0, 0.02, 0.05, and 1. For the semiconducting samples (x = 0, 0.02, and 0.05) the results below 200 K are consistent with the presence of a small gap in the quasiparticle excitation spectrum; above 200 K there is an anomalous contribution to the thermal expansion that lacks a detailed explanation, but which is probably associated with the high density of conduction electrons found in FeSi above 200 K. © 1994.