Magnetic Properties of CePtSn Under Pressure

We report on magnetic susceptibility measurements on a CePtSn single crystal under hydrostatic pressures up to 0.82 GPa. Application of hydrostatic pressure on CePtSn leaves both the Neel temperature T-N and the AF1-AF2 transition temperature T-M nearly intact. This is rather unexpected because the volume contraction was believed to be the main reason for the transformation from the antiferromagnetic Kondo metal with T-N = 7.5 CePtSn to a non-magnetic Kondo semi-metal CeNiSn G.M. Kalvius et al., Physica B 289-290, 256 (2000). The only pressure effect observed is a 25% reduction of low-temperature magnetization by the pressure of 0.82 GPa. A possible scenario for physics of CePtSn is discussed accounting for the observed pressure effects.