Article

Fabrication and Characterization of Beaded SiC Quantum Rings with Anomalous Red Spectral Shift

Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA 16802-6812, USA.
Advanced Materials (Impact Factor: 15.41). 11/2012; 24(41). DOI: 10.1002/adma.201202286
Source: PubMed

ABSTRACT Beaded SiC quantum rings can be prepared by introducing a carbonization reaction at the laser-induced Si plasma and ethanol interface (referred to as reactive laser ablation). An anomalous red spectral shift is observed when the diameter of SiC nanocrystals within the SiC quantum rings is smaller than 3 nm. Experimental results and theoretical calculations indicate that the observed anomalous red spectral shift is ascribed to the contributions from surface structures (e.g., surface composition, surface reconstruction, and exposed crystal planes).

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