文摘
The high-pressure Raman spectra of AlN nanowires have been measured up to 33.1 GPa. The phase transition from the wurtzite to rocksalt was found at about 24.4 GPa by the appearance of a new Raman signal. Above 24.4 GPa, a new Raman signal due to disorder-activated Raman scattering in the rocksalt phase was observed. The pressure coefficients, phase transition criterion, and transition path of AlN nanowires, which could be different from that of bulk AlN, are carefully discussed. The Raman signal of AlN nanowires recovered at ambient pressure from 33.1 GPa is similar to that of rocksalt-type AlN nanowires obtained previously after a high-pressure treatment to 51.1 GPa.