Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


J. Korean Phy. Soc. 2009; 55(1): 275-279

Published online July 15, 2009

Copyright © The Korean Physical Society.

Optical Properties and Electronic Subband Structures inIn$_{x}$Ga$_{1-x}$N/GaN Single Quantum Wells

D.U. Lee, J.H. You, T.W. Kim, J.H. Lee, K.H. Yoo, S.B. Bae, K.S. Lee, L.R. Ram-Mohan


An In$_{x}$Ga$_{1-x}$N/GaN single quantum well (SQW) was grown andwas investigated by X-ray diffraction (XRD), photoluminescence (PL),and Hall measurements. The In composition of the In$_{x}$Ga$_{1-x}$Nlayer was determined to be 30\% from the XRD data. The activationenergy of the excitons confined in the In$_{0.3}$Ga$_{0.7}$N/GaNSQWs, as obtained from the temperature-dependent PL spectra, was 70meV. The electron and the hole states were calculated by using amulti-band $vec {k}cdot vec {p}$ theory and considering thestrain due to the lattice mismatch and the spontaneous andpiezoelectric polarizations, and the results were compared with thePL data. The potential due to free carriers observed in the Hallmeasurement was also taken into account by solving theSchr"{o}dinger equation and the Poisson equation self-consistently.The calculated electronic structure of the In$_{0.3}$Ga$_{0.7}$N/GaNSQW showed that only one subband below the Fermi level was occupiedby the electrons. The present results help improve understanding ofthe electronic structures in In$_{x}$Ga$_{1-x}$N/GaN SQWs.

Keywords: Polarization effect, Electronic structure, In$_{x}$Ga$_{1-x}$N/GaN single quantum well