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

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We consider the dephasing rate of an electron level in a quantum dot, placed next to a fluctuating edge current in the fractional quantum Hall effect. Using perturbation theory, we show that this rate has an anomalous dependence on the bias…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Thi Kim Thanh Nguyen , Adeline Crepieux , Thibaut Jonckheere , Ai Viet Nguyen , Yeoshua Levinson , Thierry Martin

While highly successful, density functional theory is known to have limitations owing to its neglect of many-body electron-electron interactions. This neglect leads to errors in the single-particle energies, leading to underestimated band…

Materials Science · Physics 2026-04-16 John Vinson , Terrence Jach , Rainer Unterumsberger , Michael A. Woodcox , Burkhard Beckhoff

Quantum Hall edge channels offer an efficient and controllable platform to study quantum transport in one dimension. Such channels are a prospective tool for the efficient transfer of quantum information at the nanoscale, and play a vital…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 T. Krähenmann , S. G. Fischer , M. Röösli , T. Ihn , C. Reichl , W. Wegscheider , K. Ensslin , Y. Gefen , Y. Meir

We study the electronic transport through a quantum wire (QW) with a strong side coupled quantum dot (QD). We obtain a linear conductance with lateral peaks when the gate voltage, is located near the edge of the conduction band. The…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 R. Franco , E. V Anda , M. S. Figueira

We present a study of the excitations of the edge of a two-dimensional electron droplet in a magnetic field in terms of a contour dynamics formalism. We find that, beyond the usual linear approximation, the non-linear analysis yields…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 C. Wexler , Alan T. Dorsey

The photon-absorption edge in a weakly interacting one-dimensional electron gas is studied, treating backscattering of conduction electrons from the core hole exactly. Close to threshold, there is a power-law singularity in the absorption,…

Condensed Matter · Physics 2009-10-22 C. L. Kane , K. A. Matveev , L. I. Glazman

A quantum edge detector for image segmentation in optical environments is presented in this work. A Boolean version of the same detector is presented too. The quantum version of the new edge detector works with computational basis states,…

Computer Vision and Pattern Recognition · Computer Science 2014-09-11 Mario Mastriani

A general framework is proposed to tackle analytically local quantum quenches in integrable impurity systems, combining a mapping onto a boundary problem with the form factor approach to boundary-condition-changing operators introduced in…

Strongly Correlated Electrons · Physics 2013-06-17 Romain Vasseur , Kien Trinh , Stephan Haas , Hubert Saleur

We study the electron states of a chain of non-identical, vertically stacked quantum dots (QDs). We discuss how the pseudo-band formed of the ground states confined in the QDs disintegrates upon increasing the inhomogeneity of the electron…

Mesoscale and Nanoscale Physics · Physics 2017-12-06 Igor Bragar , Paweł Machnikowski

We address the electronic properties of quantum dots in the two-dimensional $\alpha-\mathcal{T}_3$ lattice when subjected to a perpendicular magnetic field. Implementing an infinite mass boundary condition, we first solve the eigenvalue…

Mesoscale and Nanoscale Physics · Physics 2020-09-08 Alexander Filusch , Holger Fehske

We discuss approximations of the vertex coupling on a star-shaped quantum graph of $n$ edges in the singular case when the wave functions are not continuous at the vertex and no edge-permutation symmetry is present. It is shown that the…

Mathematical Physics · Physics 2019-12-10 Pavel Exner , Ondrej Turek

Pre-edge features in X-ray absorption spectroscopy contain key information about the lowest excited states and thus on the most interesting physical properties of the system. In transition metal oxides they are particularly structured but…

Materials Science · Physics 2008-07-01 C. Gougoussis , M. Calandra , A. Seitsonen , Ch. Brouder , A. Shukla , F. Mauri

We have studied the single-electron transport spectrum of a quantum dot in GaAs/AlGaAs resonant tunneling device. The measured spectrum has irregularities indicating a broken circular symmetry. We model the system with an external potential…

Strongly Correlated Electrons · Physics 2009-11-10 E. Rasanen , J. Konemann , R. J. Haug , M. J. Puska , R. M. Nieminen

Within the framework of adiabatic approximation, the energy levels and direct interband light absorption in a strongly prolated ellipsoidal quantum dot are studied. Analytical expressions for the particle energy spectrum and absorption…

Mesoscale and Nanoscale Physics · Physics 2015-05-08 K. G. Dvoyan , D. B. Hayrapetyan , E. M. Kazaryan

In this paper we first derive a Coulomb Hamiltonian for electron--electron interaction in quantum dots in the Heisenberg picture. Then we use this Hamiltonian to enhance a Bloch model, which happens to be nonlinear in the density matrix.…

Mathematical Physics · Physics 2014-02-13 Brigitte Bidégaray-Fesquet , Kole Keita

We investigate the Yang-Lee edge singularity on non-planar random graphs, which we consider as the Feynman Diagrams of various d=0 field theories, in order to determine the value of the edge exponent. We consider the hard dimer model on…

High Energy Physics - Lattice · Physics 2008-11-26 D. A. Johnston

We review recent results on the linear and non-linear optical response of realistic quantum-wire structures. Our theoretical approach is based on a set of generalized semiconductor Bloch equations, and allows a full three-dimensional…

Materials Science · Physics 2009-10-30 Fausto Rossi , Elisa Molinari

The wavefronts from a point source in a solid with cubic symmetry are examined with particular attention paid to the contribution from the conical points of the slowness surface. An asymptotic solution is developed that is uniform across…

Materials Science · Physics 2007-06-25 Andrew N. Norris

We study the spectral properties of electron quantum dots (QDs) confined in 2D parabolic harmonic oscillator influenced by external uniform electrical and magnetic fields together with an Aharonov-Bohm (AB) flux field. We use the…

Mesoscale and Nanoscale Physics · Physics 2012-09-26 Sameer M. Ikhdair , Majid Hamzavi , Ramazan Sever

We measure tunnelling currents through electrostatically defined quantum dots in a GaAs/AlGaAs heterostructure connected to two leads. For certain tunnelling barrier configurations and high sample bias we find a pronounced resonance…

Mesoscale and Nanoscale Physics · Physics 2017-02-06 Tobias Krähenmann , Livio Ciorciaro , Christian Reichl , Werner Wegscheider , Leonid Glazman , Thomas Ihn , Klaus Ensslin