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This book is Yu Cao´s Master dissertation under Prof. Jena´s direction. The book discussed the growth of single and multiple AlN/GaN heterojunctions by Molecular Beam Epitaxy (MBE). Transport properties of single AlN/GaN heterojunctions have been studied. Record-low sheet resistance in single nitride heterojunctions have been achieved. Dominant scattering mechanisms in AlN/GaN heterojunctions are discussed with the support of experimental results. Shubnikov de-Haas oscillations have been observed for the first time in binary nitrides. In the study of AlN/GaN superlattices, theoretical calculation for subband energy is demonstrated under the approximation of using Airy function as the electron wavefunction. Acoustic phonon propagation across AlN/GaN superlattices are studied based on transfer matrix method. Transmission rate of acoustic phonons in AlN/GaN superlattices with different structures are modeled. Phonon filters and cavities are design according to this study with the support of simulations.

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