<link rel="stylesheet" href="styles.cf390c6bfbe7555f.css">

學術出版;;Publications

Permanent URI for this communityhdl:11536/1

收集所有交通大學研究人員與學生個人或團體所發表之各項學術著作，涵蓋期刊論文、教師專書、學位論文等項。;;Collections of Publications of NCTU Researchers and Students Like Journal Papers and Thesis.

Browse

🏛️國立陽明交通大學機構典藏

Author: search.filters.author.Chang, Wen-HaoSubject: search.filters.subject.indium compounds

Search Results

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item type:Item,
    Impacts of structural asymmetry on the magnetic response of excitons and biexcitons in single self-assembled In(Ga)As quantum rings
    (2009-08-01)
    Lin, Ta-Chun
    ;
    Lin, Chia-Hsien
    ;
    Ling, Hong-Shi
    ;
    Fu, Ying-Jhe
    ;
    Chang, Wen-Hao
    The diamagnetic shifts of neutral excitons and biexcitons confined in single self-assembled In(Ga)As/GaAs quantum rings are investigated. Unlike quantum dots, quantum rings reveal a considerably large biexciton diamagnetic shift, about two times larger than that of single excitons. Based on model calculations, we found that the inherent structural asymmetry and imperfection, combined with the interparticle Coulomb interactions, is the fundamental cause of the more extended biexciton wave function in the quantum rings. The exciton wave function tends to be localized in one of the potential valleys induced by structural imperfections of the quantum ring due to the strong localization of hole and the electron-hole Coulomb attraction, resembling the behavior in single dots. Our results suggest that the phase coherence of neutral excitons in quantum rings will be smeared out by such wave function localizations.
  • Thumbnail Image
    Item type:Item,
    Recombination lifetimes in InN films studied by time-resolved excitation-correlation spectroscopy
    (2009-11-01)
    Liu, Horng-Chang
    ;
    Hsu, Chia-He
    ;
    Chou, Wu-Ching
    ;
    Chen, Wei-Kuo
    ;
    Chang, Wen-Hao
    Recombination dynamics in degenerate InN were investigated by means of time-resolved excitation-correlation spectroscopy. The photoluminescence decay times are determined beyond the spectral response and temporal resolution limits of conventional photon-counting detectors. Spectral and temperature dependence of decay times reveal the effects of hole localizations on the recombination mechanisms. At low temperatures, the radiative lifetime tau(r) is insensitive to temperature and significantly longer than that predicted for the radiative band-to-band recombination, indicative of a transition dominated by the free-to-bound recombination without k conservation. Above a certain temperature determined by the electron concentration, we find tau(r)similar to T(3/2), as expected for the band-to-band transition when the k-selection rule holds. We determine a lower limit for the bimolecular recombination coefficient B in InN at 300 K as 5.6x10(-11) cm(3)/s.
  • Thumbnail Image
    Item type:Item,
    Size-dependent strain relaxation in InN islands grown on GaN by metalorganic chemical vapor deposition
    (2009-02-09)
    Tsai, Wen-Che
    ;
    Lin, Feng-Yi
    ;
    Ke, Wen-Cheng
    ;
    Lu, Shu-Kai
    ;
    Cheng, Shun-Jen
    We report Raman measurements on InN islands grown on GaN by metalorganic chemical vapor deposition. The Raman frequency of the InN E(2) mode is found to decrease exponentially with the island's aspect ratio, indicating a size dependent strain relaxation during the island formation. Our results suggest that most of the strain at the InN-GaN interface have been released plastically during the initial stage of island formations. After that, the residual strain of only -3.5x10(-3) is further relaxed elastically via surface islanding. The experimental data are in agreement with the strain relaxation predicted from a simplified model analysis as well as three-dimensional finite-element simulations.
  • Thumbnail Image
    Item type:Item,
    Effects of thermal annealing on the emission properties of type-II InAs/GaAsSb quantum dots
    (2009-02-02)
    Liao, Yu-An
    ;
    Hsu, Wei-Ting
    ;
    Chiu, Pei-Chin
    ;
    Chyi, Jen-Inn
    ;
    Chang, Wen-Hao
    We report the effects of thermal annealing on the emission properties of type-II InAs quantum dots (QDs) covered by a thin GaAs(1-x)Sb(x) layer. Apart from large blueshifts and a pronounced narrowing of the QD emission peak, the annealing induced alloy intermixing also leads to enhanced radiative recombination rates and reduced localized states in the GaAsSb layer. Evidences of the evolution from type-II to type-I band alignments are obtained from time-resolved and power-dependent photoluminescence measurements. We demonstrate that postgrowth thermal annealing can be used to tailor the band alignment, the wave function overlaps, and hence the recombination dynamics in the InAs/GaAsSb type-II QDs.