Advances in Energy Transfer Processes:
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In semiconductors, localized vibrational mode spectroscopy has been used successfully in identifying the sites occupied by intrinsic defects, light impurities and complexes formed by them. The measurements are most valuable when combined with other complementary techniques. We present an overview of both theoretical and experimental requirements for the observation of localized vibrational modes of impurities and defects. Our discussion is restricted to the infrared absorption and Raman scattering techniques with emphasis on the characteristics of modes caused by light impurities such as beryllium-, boron-, silicon-, and carbon- in GaAs and AlAs grown by molecular beam epitaxy (MBE). Direct evidence for C As acceptors, and the pairing of intrinsic defects with Si and Be in MBE grown GaAs at low temperatures is demonstrated. A theoretical treatment based on Greens 0function method is illustrated by the calculations of isotopic fine structure of B As lines in GaAs and the modes of nearest-neighbor and second nearest-neighbor pair defects in GaAs , AlAs and Al x Ga 1- x As .
World Scientific Publishing Co. Pte. Ltd.
Talwar, Devki N., "Advances in Energy Transfer Processes:" (2001). Physics Faculty Book Gallery. 1.