Optical Properties of Ga2Se3 under High Pressure

✍ Scribed by M. Takumi; T. Ueda; Y. Koshio; H. Nishimura; K. Nagata

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 107 KB
• Volume: 223
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/1521-3951(200101)223:1<271::aid-pssb271>3.0.co;2-2

✦ Synopsis

The optical absorption spectrum of b-Ga 2 Se 3 has been measured at pressures up to 7 GPa using a diamond anvil cell. The exciton absorption is observed in the optical absorption spectrum at ambient pressure. With increasing pressure, the exciton line shifts to the higher energy region. From the shift of the exciton line with pressure, the pressure dependence of the band gap energy (dE g /dP) is estimated to be (45 AE 4) meV/GPa at ambient pressure. This pressure coefficient agrees well with that obtained previously by photoluminescence measurements. The pressure coefficient of the band gap and the intensity of the exciton line decrease gradually with pressure, and become almost zero at 7 GPa, what suggests that a pressure induced direct-to indirect-gap semiconductor transition occurs.