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Related papers: Multi-excitonic complexes in single InGaN quantum …

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A sequence of photoluminescence spectroscopy based methods are used to rigorously identify and study all the main spectral features (more than thirty emission lines) of site controlled InGaAs/AlGaAs quantum dots (QDs) grown along [111]B in…

A transition from a cylindrical quantum dot to a highly elongated quantum dash is theoretically studied here with an atomistic approach combining empirical tight binding for single particle states and configuration interaction method for…

Mesoscale and Nanoscale Physics · Physics 2019-05-08 Michał Zieliński

We characterize the positively charged exciton (X1+) in single InGaAs quantum dots using resonant laser spectroscopy. Three samples with different dopant species (Be or C as acceptors, Si as a donor) are compared. The p-doped samples…

Mesoscale and Nanoscale Physics · Physics 2015-05-30 B. D. Gerardot , R. J. Barbour , D. Brunner , P. A. Dalgarno , A. Badolato , N. Stoltz , P. M. Petroff , J. Houel , R. J. Warburton

Single photon emission was observed from site-controlled InGaN/GaN quantum dots. The single-photon nature of the emission was verified by the second-order correlation function up to 90 K, the highest temperature to date for site-controlled…

We report on the magnetic field dispersion of the exciton spin-splitting and diamagnetic shift in single InAs/GaAs quantum dots (QDs) and dot molecules (QDMs) up to $B$ = 28 T. Only for systems with strong geometric confinement, the…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 A. Babinski , G. Ortner , S. Raymond , M. Potemski , M. Bayer , P. Hawrylak , A. Forchel , Z. Wasilewski , S. Fafard

We analyze the potential of the $c$-plane InGaN/GaN quantum dots for polarization entangled photon emission by means of an atomistic many-body framework. Special attention is paid to the impact of random alloy fluctuations on the excitonic…

Mesoscale and Nanoscale Physics · Physics 2020-09-24 Saroj Kanta Patra , Stefan Schulz

The spectral properties of one exciton trapped in a self-assembled multi-layered quantum dot is obtained using a high precision variational numerical method. The exciton Hamiltonian includes the effect of the polarization charges, induced…

Quantum Physics · Physics 2014-12-24 Mariano Garagiola , Omar Osenda

We report on resonant optical spectroscopy of self-assembled InGaAs quantum dots in which the number of electrons can accurately be tuned to N=0,1,2 by an external gate voltage. Polarization, wave vector and magnetic field dependent…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 Tim Köppen , Dennis Franz , Andreas Schramm , Christian Heyn , Johann Gutjahr , Daniela Pfannkuche , Detlef Heitmann , Tobias Kipp

Quantum dots acting as single photon emitters in the blue-green range are fabricated and characterized at cryogenic temperature. They consist in CdSe dots inserted in (Zn,Mg)Se nanowires with a thick shell. Photoluminescence spectra, decay…

Non-linear Zeeman splitting of neutral excitons is observed in composition engineered In(x)Ga(1-x)As self-assembled quantum dots and its microscopic origin is explained. Eight-band k.p simulations, performed using realistic dot parameters…

Mesoscale and Nanoscale Physics · Physics 2012-06-01 V. Jovanov , T. Eissfeller , S. Kapfinger , E. C. Clark , F. Klotz , M. Bichler , J. G. Keizer , P. M. Koenraad , M. S. Brandt , G. Abstreiter , J. J. Finley

Single lateral InGaAs quantum dot molecules have been embedded in a planar micro-cavity in order to increase the luminescence extraction efficiency. Using a combination of metal-organic vapor phase and molecular beam epitaxy samples could…

Scattering of carriers between spatially separated zero dimensional states has been observed in a system of self-assembled In_{0.55}Al_{0.45}As quantum dots. We believe the interdot tunneling is mediated by localized states below the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 H. D. Robinson , B. B. Goldberg , J. L. Merz

By the application of an in-plane magnetic field, we demonstrate control of the fine structure polarisation splitting of the exciton emission lines in individual InAs quantum dots. The selection of quantum dots with certain barrier…

We investigate the interband transitions in several ensembles of self-assembled InAs/GaAs quantum dots by using photoluminescence excitation spectroscopy under strong magnetic field. Well defined resonances are observed in the spectra. A…

We present results of correlated pseudopotential calculations of an exciton in a pair of vertically stacked InGaAs/GaAs dots. Competing effects of strain, geometry, and band mixing lead to many unexpected features missing in contemporary…

Materials Science · Physics 2012-03-08 Gabriel Bester , J. Shumway , Alex Zunger

We determine the diffusion length of excess carriers in GaN by spatially resolved cathodoluminescence spectroscopy utilizing a single quantum well as carrier collector or carrier sink. Monochromatic intensity profiles across the quantum…

Exciton fine structures in cubic III-V semiconductor GaAs, InAs and GaN quantum dots are investigated systematically and the exciton spin relaxation in GaN quantum dots is calculated by first setting up the effective exciton Hamiltonian.…

Mesoscale and Nanoscale Physics · Physics 2011-06-15 H. Tong , M. W. Wu

We present a theoretical analysis of four-wave mixing in coupled quantum dots subject to inhomogeneous broadening. For the biexciton transitions a clear signature of interdot-coupling appears in the spectra. The possibility of experimental…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Pekka Koskinen , Ulrich Hohenester

We report electron transport measurements of a silicon double dot formed in multi-gated metal-oxide-semiconductor structures with a 15-nm-thick silicon-on-insulator layer. Tunable tunnel coupling enables us to observe an excitation spectrum…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 H. W. Liu , T. Fujisawa , H. Inokawa , Y. Ono , A. Fujiwara , Y. Hirayama

The optical creation and recombination of charged biexciton and trion complexes in an (In,Ga)As/GaAs quantum dot is investigated by micro-photoluminescence spectroscopy. Photon cross-correlation measurements demonstrate the temporally…

Other Condensed Matter · Physics 2009-11-10 S. M. Ulrich , M. Benyoucef , P. Michler , N. Baer , P. Gartner , F. Jahnke , M. Schwab , H. Kurtze , M. Bayer , S. Fafard , Z. Wasilewski