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We measured the absorption spectrum of a single T-shaped, 14x6 nm lateral-sized quantum wire embedded in an optical waveguide using waveguide-transmission spectroscopy at 5 K. In spite of its small volume, the one-dimensional-exciton ground…

We consider theoretically the formation and stability of quasi-one dimensional many-body excitons in GaAs quantum wire structures under external photoexcitation conditions by solving the dynamically screened Bethe-Salpeter equation for…

Strongly Correlated Electrons · Physics 2009-10-31 S. Das Sarma , D. W. Wang

High-quality T-shaped quantum wires are fabricated by cleaved-edge overgrowth with the molecular beam epitaxy on the interface improved by a growth-interrupt high-temperature anneal. Characterization by micro-photoluminescence (PL) and PL…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Hidefumi Akiyama , Loren N. Pfeiffer , Masahiro Yoshita , Aron Pinczuk , Ken W. West

We calculate, as a function of temperature and conduction band electron density, the optical absorption of a weakly n-doped, idealized semiconductor quantum well. In particular, we focus on the absorption band due to the formation of a…

Strongly Correlated Electrons · Physics 2009-11-07 F. X. Bronold

Theoretical and numerical calculations of the optical absorption spectra of excitons interacting with longitudinal-optical phonons in quasi-2D polar semiconductors are presented. In II-VI semiconductor quantum wells, exciton binding energy…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 F. J. Rodriguez

We measured polarization-dependent photoluminescence-excitation spectra of highly uniform T-shaped quantum wires at 5 K. We attribute one peak to the 1D-exciton ground state and the continuous absorption band to 1D continuum states. These…

We use linear response theory in order to compute the light absorption spectrum, in the terahertz band, of a polariton system composed by excitons in a quantum dot very strongly coupled to the lowest photon mode of a thin micropillar. In a…

Mesoscale and Nanoscale Physics · Physics 2013-10-08 Carlos Andres Vera-Ciro , Alain Delgado , Augusto Gonzalez

A theoretical description of local absorption is proposed in order to investigate spectral variations on a length scale comparable with the extension of the relevant quantum states. A general formulation is derived within the density-matrix…

Materials Science · Physics 2009-10-31 O. Mauritz , G. Goldoni , F. Rossi , E. Molinari

We study the metal-insulator transition in individual self-assembled quantum wires and report optical evidences of metallic liquid condensation at low temperatures. Firstly, we observe that the temperature and power dependence of the single…

Strongly Correlated Electrons · Physics 2008-08-12 Benito Alen , David Fuster , Guillermo Munoz-Matutano , Juan Martinez-Pastor , Yolanda Gonzalez , Luisa Gonzalez

A new modeling way of describing the continuous absorption of electromagnetic (EM) radiation in dense partially ionized hydrogen plasma is tested in this work. It is shown that the obtained results give a possibility of calculating spectral…

Solar and Stellar Astrophysics · Physics 2012-08-14 A. A. Mihajlov , N M Sakan , V. A. Sreckovic , Y. Vitel

The superradiant decay rate and frequency shift of a Wannier exciton in a one-dimensional quantum wire are studied. It is shown that the dark mode exciton can be examined experimentally when the quantum wire is embedded in a planar…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Yueh-Nan Chen , Der-San Chuu , T. Brandes , B. Kramer

We calculate energies, oscillator strengths for radiative recombination, and two-particle wave functions for the ground state exciton and around 100 excited states in a T-shaped quantum wire. We include the single-particle potential and the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 M. H. Szymanska , P. B. Littlewood , R. J. Needs

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 investigate the FIR-absorption of short period parallel quantum wires in a perpendicular quantizing magnetic field. The external time-dependent electric field is linearly polarized along the wire modulation. The mutual Coulomb…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Andrei Manolescu , Vidar Gudmundsson

We study collective and single-particle intersubband excitations in a system of quantum wires coupled via weak tunneling. For an isolated wire with parabolic confinement, the Kohn's theorem guarantees that the absorption spectrum represents…

Condensed Matter · Physics 2009-10-28 T. V. Shahbazyan , S. E. Ulloa

We compute atomistically the heat conductance for ultra-thin pristine silicon nanowires (SiNWs) with diameters ranging from 1 to 5 nm. The room temperature thermal conductance is found to be highly anisotropic: wires oriented along the…

Materials Science · Physics 2009-01-09 Troels Markussen , Antti-Pekka Jauho , Mads Brandbyge

We study carrier interaction induced many-body effects on the excitonic optical properties of highly photoexcited one-dimensional semiconductor quantum wire systems by solving the dynamically screened Bethe-Salpeter equation using realistic…

Strongly Correlated Electrons · Physics 2009-11-07 D. W. Wang , S. Das Sarma

The absorption of surface acoustic waves (SAW's) by an array of quantum dots in which the mean level spacing Delta is larger than the sound frequency omega, the temperature T, and the phase breaking rate tau^{-1}_phi is considered. The…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Andreas Knaebchen , Ora Entin-Wohlman , Yuri Galperin , Yehoshua Levinson

At temperatures $T < {\hbar v_F}/{K_B d} \equiv T^{wire}$ the collective excitations are negligible and the spectrum of the short wire is dominated by the ''zero modes'' particle excitations. At temperature $ T > T^{wire}$ a spin polarized…

Strongly Correlated Electrons · Physics 2007-05-23 D. Schmeltzer

Using the Landauer formulation of transport theory, we predict that dielectric quantum wires should exhibit quantized thermal conductance at low temperatures in a ballistic phonon regime. The quantum of thermal conductance is universal,…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Luis G. C. Rego , George Kirczenow
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