English
Related papers

Related papers: Microscopic model of stacking-fault potential and …

200 papers

We study inhomogeneous multidimensional cosmological models with a higher dimensional space-time manifold under dimensional reduction. Stability due to different types of effective potentials is analyzed for specific configurations of…

General Relativity and Quantum Cosmology · Physics 2011-04-15 U. Guenther , A. Zhuk

We present a detailed analysis of exciton-photon interaction in a microcavity made out of a photonic crystal slab. Here we have analyzed a disk-like quantum dot where an exciton is formed. Excitonic eigen-functions in addition to their…

Quantum Physics · Physics 2009-09-17 Majid Sodagar , Milad Khoshnegar , Amin Eftekharian , Sina Khorasani

The electro-optical properties of most semiconductors and insulators of technological interest are dominated by the presence of electron-hole quasiparticles called excitons. The manipulation of these hydrogen-like quasi-particles in…

A study of the formation of excitons as a problem of two Dirac particles confined in two-layer graphene sheets separated by a dielectric when gaps are opened and they interact via a Coulomb potential is presented. We propose to observe…

Mesoscale and Nanoscale Physics · Physics 2013-07-30 Oleg L. Berman , Roman Ya. Kezerashvili , Klaus G. Ziegler

We study experimentally and theoretically the exciton-phonon interaction in MoSe2 monolayers encapsulated in hexagonal BN, which has an important impact on both optical absorption and emission processes. The exciton transition linewidth…

One of the challenges of excitonic materials is the accurate determination of the exciton binding energy and bandgap. The difficulty arises from the overlap of the discrete and continuous excitonic absorption at the band edge. Many…

We propose a double channel mechanism for the formation of charged excitons (trions); they are formed through bi- and tri-molecular processes. This directly implies that both negatively and positively charged excitons coexist in a quantum…

Materials Science · Physics 2009-09-29 M. T. Portella-Oberli , J. Berney , L. Kappei , F. Morier-Genoud , J. Szczytko , B. Deveaud

We have performed density functional theory (DFT) calculations to characterize the energetics, and the atomic and electronic structure, of stacking faults in GaN, both in the stable hexagonal wurtzite (wz) phase and in the metastable cubic…

Materials Science · Physics 2026-02-10 Zijie Wang , Mazharul M. Islam , David R. Bowler

We present a model for the disorder of the heterointerfaces in GaAs quantum wells including long-range components like monolayer island formation induced by the surface diffusion during the epitaxial growth process. Taking into account both…

Materials Science · Physics 2015-05-05 Vincenzo Savona , Wolfgang Langbein

We report on polariton states bound to defects in planar GaAs/AlAs microcavities grown by molecular beam epitaxy. The defect types relevant for the spatial polariton dynamics in these structures are cross-hatch misfit dislocations, and…

Materials Science · Physics 2012-04-16 Joanna M Zajac , Wolfgang Langbein , Maxime Hugues , Mark Hopkinson

We show that when following a simple cavity design metric, a quantum well exciton-microcavity photon coupling constant can be larger than the exciton binding energy in GaAs based optical microcavities. Such a very strong coupling…

Quantum Physics · Physics 2018-06-25 H. Zhang , N. Y. Kim , Y. Yamamoto , N. Na

The kinetics of the process of defect accumulation in rare-gas solids as a result of exciton self-trapping was studied using the selective vacuum ultraviolet photoluminescence method for monitoring of the crystal structure of the samples.…

Materials Science · Physics 2009-02-10 A. N. Ogurtsov , O. N. Bliznjuk , N. Yu. Masalitina

We have performed real and momentum space spectroscopy of exciton polariton condensates in a GaAs-based microcavity under non-resonant excitation with an intensity stabilized laser. An effective trapping mechanism is revealed, which is due…

A theory of polaritonic states is developed for a nanostructure with a wide quantum well stressed perpendicular to the growth axis of the heterostructure. The role of the $K$-linear terms appearing in the exciton Hamiltonian under the…

Mesoscale and Nanoscale Physics · Physics 2014-08-20 D. K. Loginov , A. V. Trifonov , I. V. Ignatiev

We present a systematic investigation of two-photon excitation processes in a GaAs-based microcavity in the strong-coupling regime. We observe second harmonic generation resonant to the upper and lower polariton level, which exhibits a…

Mesoscale and Nanoscale Physics · Physics 2014-08-06 Johannes Schmutzler , Marc Aßmann , Thomas Czerniuk , Martin Kamp , Christian Schneider , Sven Höfling , Manfred Bayer

Resonance dielectric response of excitons is studied for the high-quality GaAs/InGaAs heterostructures with wide asymmetric quantum wells (QWs). To highlight effects of the QW asymmetry, we have grown and studied several heterostructures…

A theoretical description of radiation-matter coupling for semiconductor-based photonic crystal slabs is presented, in which quantum wells are embedded within the waveguide core layer. A full quantum theory is developed, by quantizing both…

Soft Condensed Matter · Physics 2009-11-13 D. Gerace , L. C. Andreani

We investigated excitonic absorptions in GaAs/AlAs/GaAs single barrier heterostructure using both photocapacitance and photocurrent spectroscopies at room temperature. Photocapacitance spectra show well defined resonance peak of indirect…

Mesoscale and Nanoscale Physics · Physics 2018-02-02 Amit Bhunia , Mohit Kumar Singh , Y. Galvao Gobato , Mohamed Henini , Shouvik Datta

We introduce interatomic potentials for tungsten in the bcc crystal phase and its defects within the Gaussian Approximation Potential (GAP) framework, fitted to a database of first principles density functional theory (DFT) calculations. We…

Materials Science · Physics 2014-08-29 Wojciech J. Szlachta , Albert P. Bartók , Gábor Csányi

The theory of exciton spectrum in multi-shell hexagonal semiconductor nanotube is developed within the effective masses and rectangular potentials approximations using the method of effective potential. It is shown that the exciton binding…

Mesoscale and Nanoscale Physics · Physics 2012-10-09 O. M. Makhanets , V. I. Gutsul , N. R. Tsiupak , O. M. Voitsekhivska