Structural phase transition in Bi2Te3 under high pressure

Structural change in Bi2Te3 under high pressure up to 16.6GPa has been studied by powder x-ray diffraction. We observed two times of phase transitions at room temperature at the pressures of 8 and 14GPa, respectively. According to our preliminary result on electrical resistance, it is reasonable to suppose that superconducting transition with Tc=2.8K at the pressures of 10.2GPa is observed in phase II. On the other hand, we found anomalies of the pressure dependences of lattice parameters and volume at around 2GPa, which probably means the change in electrical structure on the Fermi surface.