论文信息 - Complete in-plane polarization anisotropy of the A exciton in unstrained A-plane GaN films

Complete in-plane polarization anisotropy of the A exciton in unstrained A-plane GaN films

Using reflectance spectroscopy, the in-plane polarization behavior of unstrained C- and A-plane GaN films is experimentally investigated. While no in-plane polarization anisotropy is observed for all three band-gap related excitons (A, B, and C) in unstrained C-plane GaN films, the A exciton is completely linearly polarized perpendicular to the c axis in unstrained A-plane GaN films. However, the B and C excitons are only partially polarized. This observation is in excellent agreement with results based on band-structure calculations using the Bir-Pikus Hamiltonian for the wurtzite crystal structure.

[1] K. Korona,et al. POLARITON EFFECTS IN REFLECTANCE AND EMISSION SPECTRA OF HOMOEPITAXIAL GAN , 1997 .

[2] M. Reiche,et al. Nitride semiconductors free of electrostatic fields for efficient white light-emitting diodes , 2000, Nature.

[3] P. Perlin,et al. Optically pumped GaN∕AlGaN separate-confinement heterostructure laser grown along the (112¯0) nonpolar direction , 2007 .

[4] D. G. Thomas,et al. Theoretical and Experimental Effects of Spatial Dispersion on the Optical Properties of Crystals , 1963 .

[5] James S. Speck,et al. Polarization anisotropy in GaN films for different nonpolar orientations studied by polarized photoreflectance spectroscopy , 2006 .

[6] Yoichi Kawakami,et al. Photoluminescence and optical reflectance investigation of semipolar and nonpolar GaN , 2007 .

[7] G. E. Pikus,et al. Symmetry and strain-induced effects in semiconductors , 1974 .

[8] Oliver Brandt,et al. Electronic band structure of wurtzite GaN under biaxial strain in the M plane investigated with photoreflectance spectroscopy , 2002 .

[9] M. Albrecht,et al. Nitride Semiconductors: Handbook on Materials and Devices , 2003 .