Electrical resistivity and effect of pressure on the thermal expansion of a single crystal of YbCu2Si2

Electrical resistivity ρ(T) and thermal expansion Δl/l were measured for the intermediate valence compound (IVC) YbCu2Si2 and its counterpart LuCu2Si2 between 4.2 K and 300 K. It was found that the thermal expansion coefficient α(T) has a negative minimum around 31 K (=Tmin) at atmospheric pressure and Tmin decreases with increasing pressure at the rate δTmin/δT = -0.45 K/kbar. © 1993