Anomalous Raman features of silicon nanowires under high pressure

Somnath Bhattacharyya; Dmitry Churochkin; Rudolph M Erasmus

doi:10.1063/1.3499297

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arXiv · 1006.0442

Anomalous Raman features of silicon nanowires under high pressure

Somnath Bhattacharyya·Dmitry Churochkin·Rudolph M Erasmus

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Abstract

The potential of silicon nanowires (SiNWs), (diameter < 10 nm) to transform into rigid bundle-like structures with distinct phonon confinement under high pressure (<= 15 GPa), instead of amorphising as per previous reports, is demonstrated using in-situ Raman spectroscopy. The newly 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 the novel structures are superior compared to other nano-structured silicon and bulk-Si in terms of increased linear modulus, more localized phonon confinement and less anharmonicity.

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Somnath Bhattacharyya, Dmitry Churochkin, Rudolph M Erasmus. 2010-07-22. Anomalous Raman features of silicon nanowires under high pressure. https://doi.org/10.1063/1.3499297

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