English
Related papers

Related papers: Direct bandgap optical transitions in Si nanocryst…

200 papers

Quantum effects at the nanometric level have been observed in many confined structures, and particularly in semiconductor quantum dots (QDs). In this work, we propose a theoretical improvement of the so-called effective mass approximation…

Mesoscale and Nanoscale Physics · Physics 2012-03-01 Baptiste Billaud , T. T. Truong

Organic molecular crystals are expected to feature appreciable electron-phonon interactions that influence their electronic properties at zero and finite temperature. In this work, we report first-principles calculations and an analysis of…

We consider theoretically a semiconductor nanostructure embedded in one-dimensional microcavity and study the modification of its electron energy spectrum by the vacuum fluctuations of the electromagnetic field. To solve the problem, a…

Mesoscale and Nanoscale Physics · Physics 2014-06-19 T. Espinosa-Ortega , O. Kyriienko , O. V. Kibis , I. A. Shelykh

Ferromagnetic proximity effect is studied in InAs nanowire (NW) based quantum dots (QD) strongly coupled to a ferromagnetic (F) and a superconducting (S) lead. The influence of the F lead is detected through the splitting of the spin-1/2…

Mesoscale and Nanoscale Physics · Physics 2010-11-03 L. Hofstetter , S. Csonka , A. Geresdi , M. Aagesen , J. Nygard , C. Schonenberger

Here we embark on a thorough investigation of the magneto-optical absorption in semiconducting {\em spherical} quantum dots characterized by a confining harmonic potential and an applied magnetic field in the symmetric gauge. This is done…

Mesoscale and Nanoscale Physics · Physics 2016-04-13 Manvir S. Kushwaha

Based on first-principles calculations, we present a quantum confinement mechanism for the band gaps of blue phosphorene nanoribbons (BPNRs) as a function of their widths. The BPNRs considered have either armchair or zigzag shaped edges on…

Materials Science · Physics 2015-06-19 Jiefeng Xie , M. S. Si , D. Z. Yang , Z. Y. Zhang , D. S. Xue

We investigated the electronic properties of strained Si/Ge core-shell nanowires along the [110] direction using first principles calculations based on density-functional theory. The diameter of the studied core-shell wire is up to 5 nm. We…

Computational Physics · Physics 2015-05-20 Xihong Peng , Paul Logan

We present time-resolved spontaneous emission measurements of single quantum dots embedded in photonic crystal waveguides. Quantum dots that couple to the photonic crystal waveguide are found to decay up to 27 times faster than uncoupled…

Quantum Physics · Physics 2008-09-25 T. Lund-Hansen , S. Stobbe , B. Julsgaard , H. Thyrrestrup , T. Sünner , M. Kamp , A. Forchel , P. Lodahl

We propose a method to modulate the bandgaps in quasi-metallic carbon nanotubes using a transverse electric field. Unlike previous investigations, we include curvature effects of the nanotubes by incorporating both $\pi$- and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. Gunlycke , C. J. Lambert , S. W. D. Bailey , D. G. Pettifor , G. A. D. Briggs , J. H. Jefferson

Raman spectra and electrical conductance of individual, pristine, suspended, metallic single-walled carbon nanotubes are measured under applied gate potentials. The G- band is observed to downshift with small applied gate voltages, with the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Adam W. Bushmaker , Vikram V. Deshpande , Scott Hsieh , Marc W. Bockrath , Stephen B. Cronin

With the help of a multi-configurational Green's function approach we simulate single-electron Coulomb charging effects in gated ultimately scaled nanostructures which are beyond the scope of a selfconsistent mean-field description. From…

Other Condensed Matter · Physics 2007-05-23 K. M. Indlekofer , J. Knoch , J. Appenzeller

In this work we study the strong confinement effects on the electromagnetic response of metallic nanoparticles. We calculate the field enhancement factor for nanospheres of various radii by using optical constants obtained from both…

Mesoscale and Nanoscale Physics · Physics 2018-02-20 Mario Zapata-Herrera , Jefferson Flórez , Angela Camacho , Hanz Y. Ramirez

We demonstrate the ability to control the spontaneous emission dynamics of self-assembled quantum dots via the local density of optical modes in 2D-photonic crystals. We show that an incomplete 2D photonic bandgap is sufficient to…

Quantum Physics · Physics 2007-05-23 A. Kress , F. Hofbauer , N. Reinelt , H. J. Krenner , R. Meyer , G. Boehm , J. J. Finley

Although the direct or indirect nature of the bandgap transition is an essential parameter of semiconductors for optoelectronic applications, the understanding why some of the conventional semiconductors have direct or indirect bandgaps…

Materials Science · Physics 2019-01-02 Lin-Ding Yuan , Hui-Xiong Deng , Shu-Shen Li , Jun-Wei Luo , Su-Huai Wei

1-loop quantum corrections are shown to induce large effects on the refraction index n inside a graphene strip in the presence of an external magnetic field B orthogonal to it. To this purpose, we use the tools of Quantum Field Theory to…

High Energy Physics - Phenomenology · Physics 2014-07-09 Olivier Coquand , Bruno Machet

We propose a scheme in which broadband nanostructures allow to generate squeezed light and entanglement of quantum emitters that are extremely far detuned. It is shown that the reduced fluctuations of the electromagnetic field arising from…

Quantum Physics · Physics 2015-06-19 Harald R. Haakh , Diego Martín-Cano

The renormalization of the band structure at zero temperature due to electron-phonon coupling is investigated in diamond, BN, LiF and MgO crystals. We implement a dynamical scheme to compute the frequency-dependent self-energy and the…

In this work, using self-consistent tight-binding calculations, for the first time, we show that a direct to indirect bandgap transition is possible in an armchair graphene nanoribbon by the application of an external bias along the width…

Mesoscale and Nanoscale Physics · Physics 2015-05-19 Kausik Majumdar , Kota V. R. M. Murali , Navakanta Bhat , Yu-Ming Lin

We study a 2D mesoscopic ring with an anisotropic effective mass considering surface quantum confinement effects. Consider that the ring is defined on the surface of a cone, which can be controlled topologically and mapped to the 2D ring in…

Mesoscale and Nanoscale Physics · Physics 2025-10-28 Francisco A. G. de Lira , Luís Fernando C. Pereira , Edilberto O. Silva

alpha-Sn has recently been attracting significant interest due to its unique electronic properties. However, this allotrope of Sn is stable only below 13 {\deg}C and alternative options to the conventional stabilization by epitaxial growth…