Preparation and pressure-induced semiconductor-metal transition of CrSi_2 nanocrystals

摘要

Semiconducitng chromium disilicide (CrSi_2) nanocrystals were prepared by the arc plasma method, and characterized by X-ray diffraction and transmission electron microscopy. The pressure-induced semiconductor-metal transition in CrSi_2 nanocrystals was investigated in a diamond anvil cell by electrical resistance measurements at high pressure. The pressure dependence of resistance at 4room temperature in the pressure range of 0-10 GPa reveals an exponential decrease up to 3.2 GPa, indicating a linear closing of the energy gap, followed by an almost pressure-independent metallic regime. This phase transition is discussed in terms of previous band structure calculations.