Lattice Vibrational Modes in Si/Ge Core-shell Nanowires

2012/07/02 by Shih-Ming Huang, Shouting Huang, Yang Li +3
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mechanical and Optical Resonators #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Nanowire Synthesis and Applications #Silicon Nanostructures and Photoluminescence #cond-mat.mes-hall #cond-mat.mtrl-sci

paper · pdf · doi:10.48550/arxiv.1207.0527

7 pages and 6 figures

arxiv created 2012/07/02 · openalex publication_date 2012/07/02 · arxiv updated 2012/07/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We present a first-principles study on lattice vibrational modes of Si/Ge core-shell nanowires (NWs). In addition to quantum confinement, the internal strain induced by the lattice mismatch between core and shell contributes to significant frequency shifts of characteristic optical modes. More importantly, our simulation shows that these frequency shifts can be detected by Raman scattering experiments, providing convenient and nondestructive ways to obtain structural information of core-shell materials. Meanwhile, another type of collective modes, radial breathing modes (RBMs), are identified in Si-core/Ge-shell NWs and their frequency dependence is explained by an elastic media model.

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