Spectra And Optical Properties Of One-dimensional Semiconductor Nanowire System

Low dimensional semiconductor system, such as quantum well (QW), superlattice (SL), quantum wire (QWR) and quantum dot (QD), et al., were investigated extensively lately, involving the fundamental physical properties, materials fabrication and devices development. The interest in one-dimensional (ID) QWRs is fueled and fanned by its potential abundant physical phenomena and prospects in optoelectronics application. In this dissertation, the optical and electronic properties in typical direct band-gap III-VandII-A/I quasi-1D system within the different spectral region were studied. The details are as follows:1. Quasi-1D features in carrier transport, recombination and emission, et al., were studied in the V-grooved QWR samples modified by selective ion-implantation and rapidly thermal annealing, by means of Micro-photoluminescence (PL) and magneto-transport measurement. The localized 1D exciton behavior was observed in low temperature.2. The x-y spatially-resolved mapping of polarized Raman scattering spectra from a single tetrapod-like ZnO nanostructure were proposed and performed, with different polarized scattering configuration by utilizing the intrinsic geometry configuration. The resonant Raman scattering spectra were redistributed by tuning the energy band modulated by the temperature; a transformation behavior from incoming to outgoing resonant Raman scattering process was also observed. In addition, detail discussions were provided to explain the LO phonon Raman shift with increasing the temperature.3. To deeply reveal the energy band structure in well-aligned 1D ZnO nanorods, both one-photon- and two-photon-induced PL, with different transition selection rules, were performed in detail. Due to two-photon absorption strongly relies on the excitation power, three nonlinear optical absorption processes in different power density regime and band filling effect related to the many-body interaction among excitons,were traced in detail. Furthermore, a two-photon-induced PL resonant effect was confirmed by tuning the excitation wavelength from below the middle of the band-gap to above it, therefore we could get further insight of the band structures in ZnO nanorods.4. The confocal mapping Micro-spectral techniques, in conjunction with distinct low-dimensional structure and/or spectral features of the samples produced by different fabrication methods, were performed to characterize the single nanostructure.