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Related papers: The X-ray edge singularity in Quantum Dots

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We have investigated edge modes of different multipolarity sustained by quantum dots submitted to external magnetic fields. We present a microscopic description based on a variational solution of the equation of motion for any axially…

Condensed Matter · Physics 2009-10-30 E. Lipparini , N. Barberan , M. Barranco , M. Pi , Ll. Serra

Single-particle methods based on Kohn-Sham unoccupied states to describe near-edge X-ray absorption (XAS) spectra are routinely applied for the description of K-edge spectra, as there is no complication due to spin-orbit (SO) coupling. L-…

Materials Science · Physics 2026-02-26 Esther A. B. Johnsen , Naoki Horiuchi , Toma Susi , Michael Walter

In this paper the authors analyse near-edge absorption of x rays in noncentrosymmetric crystals. The work is motivated by recent observations of x-ray dichroic effects which stems from parity-nonconserving electron interactions. We provide…

Condensed Matter · Physics 2009-11-07 Paolo Carra , Andres Jerez , Ivan Marri

The self-assembled quantum dot with lens domain has rotational symmetry but it is intrinsically asymmetric when the electron moves perpendicularly to its circular base, {\it i. e.} along the rotational axis. To characterize this asymmetry,…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 Arezky H. Rodríguez , L. Meza-Montes

We have investigated theoretically the interaction between individual quantum dot with broken inversion symmetry and electromagnetic field of a single-mode quantum microcavity. It is shown that in the strong coupling regime the system…

Mesoscale and Nanoscale Physics · Physics 2016-10-05 I. G. Savenko , O. V. Kibis , I. A. Shelykh

We study Fermi edge singularities in photo-absorption spectra of generic mesoscopic systems such as quantum dots or nanoparticles. We predict deviations from macroscopic-metallic behavior and propose experimental setups for the observation…

Mesoscale and Nanoscale Physics · Physics 2009-08-12 M. Hentschel , D. Ullmo , H. U. Baranger

The Yang-Lee edge singularity is an intriguing critical phenomenon characterized by nonunitary field theory. However, its experimental realization for interacting many-body systems remains elusive. We show that Yang-Lee edge singularities,…

Quantum Gases · Physics 2025-02-25 Ming-Chu Lu , Shun-Hui Shi , Gaoyong Sun

The quantum dot asymmetrically coupled to the external leads has been analysed theoretically by means of the equation of motion (EOM) technique and the non-crossing approximation (NCA). The system has been described by the single impurity…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 M. Krawiec , K. I. Wysokinski

We formulate the problem of the Fermi Edge Singularity in non-equilibrium states of a Fermi gas as a matrix Riemann-Hilbert problem with an integrable kernel. This formulation is the most suitable for studying the singular behavior at each…

Quantum Gases · Physics 2011-07-05 E. Bettelheim , Y. Kaplan , P. Wiegmann

We investigate experimentally and theoretically few-particle effects in the optical spectra of single quantum dots (QDs). Photo-depletion of the QD together with the slow hopping transport of impurity-bound electrons back to the QD are…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Arno Hartmann , Yann Ducommun , Eli Kapon , Ulrich Hohenester , Elisa Molinari

Recent photoabsorption measurements have revealed a rich fine structure in the collective charge-density excitation spectrum of few-electron quantum dots in the presence of magnetic fields. We have performed systematic computational studies…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 C. A. Ullrich , G. Vignale

The Yang-Lee edge singularity is a quintessential nonunitary critical phenomenon accompanied by anomalous scaling laws. However, an imaginary magnetic field involved in this critical phenomenon makes its physical implementation difficult.…

Statistical Mechanics · Physics 2022-06-07 Norifumi Matsumoto , Masaya Nakagawa , Masahito Ueda

We present noise measurements of self-assembled InAs quantum dots at high magnetic fields. In comparison to I-V characteristics at zero magnetic field we notice a strong current overshoot which is due to a Fermi-edge singularity. We observe…

Mesoscale and Nanoscale Physics · Physics 2013-08-08 N. Maire , F. Hohls , T. Luedtke , K. Pierz , R. J. Haug

In perturbation theory, the spectral densities of two-point functions develop non-integrable threshold singularities at higher orders. In QCD, such singularities emerge when calculating the diagrams in terms of the pole quark mass, and they…

High Energy Physics - Phenomenology · Physics 2021-01-20 Dmitri Melikhov , Silvano Simula

We rediscuss a nonequilibrium x-ray edge problem which in recent publications led to discrepancies between the results of the perturbative and of an extended Nozieres-De Dominicis approach. We show that the this problem results from an…

Strongly Correlated Electrons · Physics 2009-11-07 Bernd Braunecker

Consider a sequence of finite regular graphs (GN) converging, in the sense of Benjamini-Schramm, to the infinite regular tree. We study the induced quantum graphs with equilateral edge lengths, Kirchhoff conditions (possibly with a non-zero…

Spectral Theory · Mathematics 2019-06-18 Maxime Ingremeau , Mostafa Sabri , Brian Winn

We consider the inverse problem of determining the density coefficient appearing in the wave equation from separated point source and point receiver data. Under some assumptions on the coefficients, we prove uniqueness results.

Analysis of PDEs · Mathematics 2019-06-24 Manmohan Vashisth

In this article, the interaction of an arbitrary number of quantum dots, behaving as artificial molecules, with different energy levels and multi-mode electromagnetic field is studied. We make the assumption that each quantum dot can be…

Quantum Physics · Physics 2015-09-30 Amir Hossein Sadeghi , Ali Naqavi , Sina Khorasani

We calculate the x-ray absorption spectra of liquid water at ambient conditions and of hexagonal ice close to melting, using a static GW approach that includes approximately local field effects. Quantum dynamics of the nuclei is taken into…

Chemical Physics · Physics 2015-06-04 Lingzhu Kong , Xifan Wu , Roberto Car

We investigate theoretically the resonant inelastic x-ray scattering (RIXS) at the $K$ edge of Si on the basis of an ab initio calculation. We calculate the RIXS spectra with systematically varying transfered-momenta, incident-photon energy…

Materials Science · Physics 2007-05-23 Yunori Nisikawa , Manabu Usuda , Jun-ichi Igarashi