Detailed understanding of the excitation-intensity dependent photoluminescence of ZnO materials: Role of defects

Rao, Prasada T and Goswami, GK and Nanda, KK (2014) Detailed understanding of the excitation-intensity dependent photoluminescence of ZnO materials: Role of defects. In: JOURNAL OF APPLIED PHYSICS, 115 (21).

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Abstract

The photoluminescence (PL) of ZnO is shown to be dependent on the excitation intensity (EI) of the laser, and the substantial shift observed in the band to band transition is attributed to the heating effect. In order to understand this phenomenon in detail, we investigate the EI dependent PL of various ZnO samples systematically from liquid nitrogen (LN) to room temperature by varying the laser power. Some of the samples exhibit substantial red shift in the band to band transition with increasing EI even in LN environment, negligible effect is observed for others. Hence, our results strongly suggest that the EI dependent PL is not a characteristic of all ZnO samples. This indicates that laser-induced heating effect is not the dominant factor that governs the shifts in the PL spectra. Rather, the defect level excitation accounts for such observation. (C) 2014 AIP Publishing LLC.

Item Type:	Journal Article
Publication:	JOURNAL OF APPLIED PHYSICS
Publisher:	AMER INST PHYSICS
Additional Information:	Copyright for this article belongs to the AMER INST PHYSICS, CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA
Department/Centre:	Division of Chemical Sciences > Materials Research Centre
Date Deposited:	17 Jul 2014 05:45
Last Modified:	17 Jul 2014 05:45
URI:	http://eprints.iisc.ac.in/id/eprint/49411

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