High pressure induced superconductivity

We have developed complex extreme condition of very low temperature down to 30 mK and ultra high pressure exceeding 200 GPa by assembling compact diamond anvil cell (DAC) on a powerful He-3/He-4 dilution refrigerator. We have also developed measuring techniques of electrical resistance, magnetization and optical measurement for the sample confined in the sample space of the DAC. Using the newly developed apparatus and techniques, we have searched for superconductivity in various materials under pressure. In this paper, we will shortly review our newly developed experimental apparatus and techniques and discuss a few examples of pressure induced superconductivity which were observed recently. (C) 2003 Elsevier B.V. All rights reserved.