Oscillating spectra of polar IO and SO phonons and electron-IO and SO phonon couplings in a freestanding wurtzite quantum wire

By employing the transfer matrix method, the polar interface optical (IO) and surface optical (SO) phonon modes and the corresponding Frohlich electron-phonon interaction Hamiltonians in a freestanding multishell wurtzite cylindrical quantum wire (QWR) are derived and studied under the dielectric continuum approximation and Loudon's uniaxial crystal model. The present theoretical scheme can be looked on as a generalization of the previous studies regarding the IO phonon modes in quasi-one-dimensional (Q1D) wurtzite QWRs with a certain layer-number. Numerical calculations on a freestanding wurtzite GaN/AlN QWR are performed. The degenerating behaviors of the IO and SO phonon modes in the freestanding wurtzite QWR seem prominent in contrast to the situation of Q1D wurtzite QWR with infinite polar matrix. The calculations of the electron-phonon coupling function show that the high-frequency IO phonon branch and SO mode play a more important role in the electron-phonon interaction. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimPhysics, Condensed MatterSCI(E)0ARTICLE81775-178424