Anomalous thermal expansion of Ce(Ru1-xRhx)2Si2 under high pressure

Thermal expansion coefficients α(T) of single-crystalline Ce(Ru1-xRhx)2Si2 (x=0.03, 0.1) have been measured under pressure up to 20 kbar in the temperature range, 2<T<300 K. It is found that the temperature (=Tm) of α-maximum of x=0.03, which may be around 2 K ar 1 bar, increases largely with increasing pressure and the anomaly at Tm tends to disappear at high pressure. A minimum in the α(T) curve of x=0.03 is observed around 70 K at 1 bar, which is attributed to the negative contribution of crystal electric field splitting to α. The minimum disappears by applying pressure. The results will be discussed in connection with Kondo effect and crystal electric field splitting. (orig.)