Author: Anne Catherine SchaeferPublisher:
ISBN: 9780591195774
Category :
Languages : en
Pages :
Book Description
Mechanisms of the Low Density Nonlinear Optical Response of Excitons in Gallium Arsenide and the Study of Exciton Transport
Author: Anne Catherine SchaeferPublisher:
ISBN: 9780591195774
Category :
Languages : en
Pages :
Book Description
American Doctoral Dissertations
Author: Publisher:
ISBN:
Category : Dissertation abstracts
Languages : en
Pages : 872
Book Description
Transient Nonlinear Spectroscopy of InAs Quantum Dots
Author: Anthony Stephen LenihanPublisher:
ISBN:
Category :
Languages : en
Pages : 332
Book Description
Research in Progress
Author: Effects of Optically Induced Coherences and Non-radiative Coherences in the Nonlinear Optical Response of Gallium Arsenide
Author: Kyle Bernard FerrioGallium Arsenide
Author: John Sydney BlakemorePublisher: Springer Science & Business Media
ISBN: 9780883185254
Category : Gallium arsenide
Languages : en
Pages : 422
Book Description
Ultrafast Nonlinear Optical Response of Fano Resonances in Gallium Arsenide Under High Magnetic Field
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 8
Book Description
Fano interference results from the coupling between a discrete energy level and a continuum of states whose energies overlap. In the linear absorption spectrum, a Fano resonance manifests itself in an asymmetric lineshape with a minimum at the energy where the contributions of the discrete state and the continuum interfere destructively. Using femtosecond spectroscopy, the authors study for the first time, the dynamics of the coherent emission from Fano resonances and compare it to that from an isolated Lorentzian line. They find that despite the very narrow frequency lineshape, the coupling to the continuum induces an almost instantaneous nonlinear optical response. Experiments are carried out in bulk GaAs, where an applied magnetic field leads to the formation of discrete magneto-exciton states. The higher-order magneto-excitons energetically overlap with the 1-dimensional continua of states with k parallel to the field and Fano resonances are formed. The zero field absorption spectrum of the sample shows that the heavy hole (hh) and light hole (lh) exciton resonances are split due to uniaxial strain. The typical Fano lineshape is clearly observed both for hh and lh magneto-excitons at B = 10T. The temporal behavior of the polarization stimulated from Fano and Lorentzian resonances is studied by transient four-wave-mixing (FWM) experiments with co-circularly polarized 100-fs pulses.
Physics Briefs
Author: Exciton Dynamics in Lead Halide Perovskite Nanocrystals
Author: Bernhard Johann BohnPublisher: Springer Nature
ISBN: 303070940X
Category : Science
Languages : en
Pages : 169
Book Description
Less than a decade ago, lead halide perovskite semiconductors caused a sensation: Solar cells exhibiting astonishingly high levels of efficiency. Recently, it became possible to synthesize nanocrystals of this material as well. Interestingly; simply by controlling the size and shape of these crystals, new aspects of this material literally came to light. These nanocrystals have proven to be interesting candidates for light emission. In this thesis, the recombination, dephasing and diffusion of excitons in perovskite nanocrystals is investigated using time-resolved spectroscopy. All these dynamic processes have a direct impact on the light-emitting device performance from a technology point of view. However, most importantly, the insights gained from the measurements allowed the author to modify the nanocrystals such that they emitted with an unprecedented quantum yield in the blue spectral range, resulting in the successful implementation of this material as the active layer in an LED. This represents a technological breakthrough, because efficient perovskite light emitters in this wavelength range did not exist before.
Author: