Journal ArticleDOI
Pure dephasing and phonon dynamics in GaAs- and GaN-based quantum dot structures: Interplay between material parameters and geometry
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TLDR
In this article, the pure dephasing of excitons in quantum dot structures due to their interaction with acoustic phonons as well as the spatiotemporal dynamics of the created nonequilibrium phonon population is studied theoretically.Abstract:
The pure dephasing of excitons in quantum dot structures due to their interaction with acoustic phonons as well as the spatiotemporal dynamics of the created nonequilibrium phonon population is studied theoretically. The theory is applied to GaAs- as well as GaN-based heterostructures. A detailed analysis of the interplay between different material parameters, different quantum dot geometries, and different electric fields is presented. The optical polarization induced by an ultrashort laser pulse exhibits a characteristic nonexponential behavior: it decays on a pico- or subpicosecond time scale to a value that strongly depends on temperature, structure, and material parameters and is then retained until, on a typically much longer time scale, it finally decays because of electron-hole recombination or transitions to other states. We find that, in general, the remnant optical polarization is much higher in the GaAs-based structures than in the GaN-based structure mainly because of the strongly enhanced piezoelectric coupling in GaN quantum dots. The optical excitation also leads to the buildup of a phonon population consisting of a polaron part that remains localized in the region of the quantum dot and a traveling part that leaves the dot region at the speed of sound. This traveling part exhibits characteristic anisotropies reflecting both the anisotropy of the quantum dot structure and of the coupling matrix elements.read more
Citations
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Theory of the linear and nonlinear optical properties of semiconductor microcrystallites
TL;DR: In the limit of a QD much smaller than the bulk exciton size, the linear spectrum will be a series of lines, and the phonon broadening of these lines is considered.
Journal ArticleDOI
Real-time path integrals for quantum dots: Quantum dissipative dynamics with superohmic environment coupling
Journal ArticleDOI
The role of acoustic phonons for Rabi oscillations in semiconductor quantum dots
TL;DR: In this article, the damping of Rabi oscillations in quantum dots as well as the renormalization of the carrier-light coupling due to the interaction with longitudinal acoustic phonons are studied as a function of temperature and laser pulse parameters.
Journal ArticleDOI
Single Photons from a Hot Solid-State Emitter at 350 K
TL;DR: In this article, single-photon emission from an isolated state in a position-controlled GaN nanowire quantum dot at an unpreceded temperature was reported, which is the first single photon emission from a quantum two-level system.
Journal ArticleDOI
The role of phonons for exciton and biexciton generation in an optically driven quantum dot.
TL;DR: This review discusses the influence of phonons on three basically different optical excitation schemes that can be used for the preparation of exciton, biexciton and superposition states and compares the performance of the schemes for state preparation.
References
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Journal ArticleDOI
A Quantum Dot Single-Photon Turnstile Device
Peter Michler,Alper Kiraz,Christoph Becher,Winston V. Schoenfeld,Pierre Petroff,Lidong Zhang,E. L. Hu,Atac Imamoglu,Atac Imamoglu +8 more
TL;DR: Using pulsed laser excitation of a single quantum dot, a single- photon turnstile device that generates a train of single-photon pulses was demonstrated.
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Control of Chemical Reactions by Feedback-Optimized Phase-Shaped Femtosecond Laser Pulses
TL;DR: Tailored femtosecond laser pulses from a computer-controlled pulse shaper were used to optimize the branching ratios of different organometallic photodissociation reaction channels, showing that two different bond-cleaving reactions can be selected, resulting in chemically different products.
Journal ArticleDOI
Theory of Light Absorption and Non-Radiative Transitions in F-Centres
Kun Huang,Avril Rhys +1 more
TL;DR: In this paper, a quantitative theory for the shapes of the absorption bands of F -centres is given on the basis of the Franck-Condon principle, and it is shown that the absorption constant as a function of frequency and temperature can be expressed in terms of Bessel functions with imaginary arguments.
Journal ArticleDOI
k⋅p method for strained wurtzite semiconductors
Shun Lien Chuang,C. S. Chang +1 more
TL;DR: In this paper, the authors derived the effective mass Hamiltonian for wurtzite semiconductors, including the strain effects, using the k-ensuremath{\cdot}p perturbation method, which is then checked with that derived using an invariant method based on the Pikus-Bir model.
Journal ArticleDOI
Ultralong Dephasing Time in InGaAs Quantum Dots
Paola Borri,Wolfgang Werner Langbein,S. Schneider,Ulrike Woggon,Roman Sellin,D. Ouyang,Dieter Bimberg +6 more
TL;DR: Between 7 and 100 K the polarization decay has two distinct components resulting in a non-Lorentzian line shape with a lifetime-limited zero-phonon line and a broadband from elastic exciton-acoustic phonon interactions.