at High Pressure*

Tin oxide (SnO₂) is one of the most widely used n-type transparent conducting oxide materials, which has attracted increasing interest due to its outstanding electrical and optical properties for potential applications. We present a detailed investigation on pressure-induced structural, electronic, and optical transitions of SnO₂ to 60 GPa, using a diamond anvil cell, micro-confocal Raman spectroscopy, infrared absorption, reflectivity, and electrical resistance measurements. The results indicate that a wide band gap (Eg=3.6 eV) n-type semiconductor undergoes a semiconductor to insulator transition at ~18 GPa. Furthermore, we will present the temperature dependent resistance changes and photoconductivity with different power density at high pressures.