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Volume 60, Number 11, 2010¸ 11Z4, pp. 1220∼1223

New Physics: Sae Mulli (The Korean Physical Society), DOI: 10.3938/NPSM.60.1220

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Optical Characteristics of High-efficiency 440 nm Dip-shaped InGaN/GaN Quantum Well Structures

Seoung-Hwan Park

^∗

Department of Electronics Engineering, Catholic Univ. of Daegu, Gyeongsan 712-702 (Received 1 September, 2010 : revised 4 October, 2010 : accepted 15 November, 2010)

The optical characteristics of 440 nm dip-shaped InGaN/GaN quantum well (QW) structures were studied using multi-band effective mass theory. The results were compared with those of con- ventional single InGaN/GaN QW structures. The transition wavelength gradually decreases with increasing carrier density due to the screening effect. The rate of decrease of the transition wave- length for the dip-shaped InGaN/GaN QW structure is smaller than that of the single InGaN/GaN QW structure. Also, the spontaneous emission peak of the dip-shaped InGaN/GaN QW structure increases by about 20 %, compared to that of the single InGaN/GaN QW structure. This can be explained by the fact that optical matrix element for the dip-shaped InGaN/GaN QW structure is enhanced due to a reduction in the internal field effect.

PACS numbers: 42.55.Px, 42.60.-v, 71.22.+i, 72.80.Ey

Keywords: InGaN, GaN, Quantum well, 440 nm, Dip-shaped quantum well

∗E-mail: [email protected]

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