Pressure-induced superconductivity in symple metals

Experimental results in search for pressure-induced superconductivity are reviewed. Typical examples are simple inorganic and organic molecular crystals, magnetic metals, and elements. 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. Using the newly developed apparatus and techniques, we have studied superconductivity in various materials in various pressure range. In this paper, we will shortly review our newly developed experimental apparatus and techniques and discuss about examples of pressure-induced superconductivity in simple metals.