Chapter 3 - Optical properties of highly excited (Al, In) GaN epilayers and heterostructures

• Published in: Handbook of Thin Films, Five-Volume Set pp. 117 - 186
• Main Authors: Bidnyk, Sergiy, J. Schmidt, Theodore, Song, Jin-Joo
• Format: Book Chapter
• Language: English
• Published: Elsevier Inc 2002
• ISBN: 0125129084; 9780125129084
• DOI: 10.1016/B978-012512908-4/50053-9

This chapter explains many issues related to gain mechanisms, pump-probe experiments, microstructure lasing, imaging, and high-temperature optical properties of the material system, as well as provides some background information on the general properties of III-nitride thin films. The capacity of optical storage is limited by the spot size of the laser beam. The minimum spot size to which a laser can be focused is proportional to the wavelength of the laser light. Because of the shorter emission wavelength of lasers based on GaN thin films, storage and high-resolution printing are natural choices for GaN-laser-diode (LD) applications. To lower production costs, shorter wavelength and higher power LDs are necessary. There are some limitations, however, as to how short the wavelength needs to be. The organic photoreceptors used in printers should be sensitive to the laser wavelengths, and expensive optics should not be used. At low temperatures, near-band-edge luminescence spectra observed from most GaN samples are dominated by strong, sharp emission lines that result from the radiative recombination of free and bound excitons.