Raman Characterization of High-Pressure Phase Transition in AlN Nanowires
SHEN Long-hai1, LI Qian1, WU Li-jun1, MA Yan-mei2, CUI Qi-liang2
1. School of Science, Shenyang Ligong University, Shenyang 110159, China 2. State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China
Abstract：High-pressure phase transition of AlN nanowires was investigated in the range of 0～33.1 GPa by in situ Raman spectrum method in diamond anvil cell (DAC). The A1(LO) vibration mode exhibits considerably asymmetry and broadening, indicating the occurrence of wurtzite-to-rocksalt phase transition. The Raman signal of high-pressure phase can be assigned to the disorder activated Raman scattering of rocksalt AlN. After fully releasing pressure, the Raman characterization of high-pressure phase was quenched. According to the pressure dependence of phonon frequency of AlN nanowires, the difference of transiton path between AlN nanowires and bulk materials was discussed and the mode Grüneisen parameters were determined.
[1] Ueno M, Onodera A, Shimomura O, et al. Physical Review B, 1992, 45: 10123. [2] Xia Q, Xia H, Ruoff A L. Journal of Appllied Physics, 1993, 73: 8198. [3] Uehara S, Masamoto T, Onodera A, et al. Journal of Physics and Chemistry of Solids, 1997, 58: 2093. [4] Shen L H, Li X F, Zhang J, et al. Applied Physics A, 2006, 84: 73. [5] Shi S C, Chen C F, Chattopadhyay S, et al. Advanced Function Materials, 2005, 15: 786. [6] Tang Y B, Cong H T, Zhao Z G, et al. Applied Physics Letters, 2005, 86: 153104. [7] Liu C, Hu Z, Wu Q, et al. Journal of the American Chemical Society, 2005, 127: 1318. [8] Manjón F J, Errandonea D, Garro N, et al. Physical Review B, 2008, 77: 205204. [9] Shen L H, Li X F, Ma Y M, et al. Applied Physics Letters, 2006, 89: 141903. [10] Halshal M P, Harmer P, Parbrook P, et al. Physical Review B, 2004, 69: 235207. [11] Pinquier C, Demangeot F, Frandon J, et al. Physical Review B, 2006, 73: 115211. [12] Cai J, Chen N. Physical Review B, 2007, 75: 134109.
