Anomalous Raman features of silicon nanowires under high pressure

作者：Bhattacharyya Somnath^*; Churochkin Dmitry; Erasmus Rudolph M

来源：Applied Physics Letters, 2010, 97(14): 141912.

DOI：10.1063/1.3499297

The potential of silicon nanowires (SiNWs), (diameter<10nm) to transform into rigid bundlelike structures with distinct phonon confinement under high pressure (<= 15GPa), instead of amorphizing as per previous reports, is demonstrated using in situ Raman spectroscopy. The observed splitting of the second order transverse optical (2TO) Raman mode into 2TO (L) and 2TO (W) phonon modes at >= 5 GPa establishes a highly anisotropic and mode-dependent pressure response of these SiNWs. Properties of these structures are superior compared to other nanostructured silicon and bulk-Si in terms of increased linear modulus, more localized phonon confinement, and less anharmonicity.

• 出版日期2010-10-4