THE ELECTRICAL-RESISTANCE OF PUSB UNDER HIGH-PRESSURE

A new experimental set-up with a Bridgman-type high pressure cell in a closed containment allows resistance measurements on highly radioacti ve materials. We present results of high pressure, low temperature stu dies on PuSb single crystals in the pressure range to 25 GPa and at te mperatures between 1.3 K and 300 K. As pressure on PuSb is increased, its Neel temperature and the transition temperature to the ferromagnet ic ground state are increased. In the pressure range from 10 to 15 GPa , we observed a strong decrease in the resistance associated with the crystallographic phase transition from the B1 (NaCl) to the B2 (CsCl) structure. The high pressure phase appears to be non-magnetic.