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Related papers: Size effects on excitons in nano-rings

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The Aharonov-Bohm and superradiant effect on the redaitive decay rate of an exciton in a quantum ring is studied. With the increasing of ring radius, the exciton decay rate is enhanced by superradiance, while the amplitude of AB oscillation…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Y. N. Chen , D. S. Chuu

We calculate the diameter and chirality dependences of the binding energies, sizes, and bright-dark splittings of excitons in semiconducting single-wall carbon nanotubes (SWNTs). Using results and insights from {\it ab initio} calculations,…

Materials Science · Physics 2009-11-11 Rodrigo B. Capaz , Catalin D. Spataru , Sohrab Ismail-Beigi , Steven G. Louie

The difficulty of describing excitons in semiconducting SWNTs analytically lies with the fact that excitons can neither be considered strictly 1D nor 2D objects. However, the situation changes in the case of metallic nanotubes where, by…

Mesoscale and Nanoscale Physics · Physics 2019-01-29 L. Shan , M. Agarwal , E. G. Mishchenko

Nanowire quantum dots, i.e., heterostructures consisting of an axial insertion of low bandgap semiconductor within large band gap semiconductor nanowire, attract interest due to their emerging applications in the field of quantum…

Mesoscale and Nanoscale Physics · Physics 2024-09-02 P. Baranowski , M. Zielinski , M. Szymura , N. Zawadzka , R. Paslawska , M. Wojcik , S. Kret , S. Chusnutdinow , P. Wojnar

Using an approximate time-dependent density functional theory method, we calculate the absorption and luminescence spectra for hydrogen passivated silicon nanoscale structures with large aspect ratio. The effect of electron confinement in…

Materials Science · Physics 2009-09-27 Y. Wang , R. Q. Zhang , Th. Frauenheim , T. A. Niehaus

Atomistically detailed computational studies of nanocrystals, such as those derived from the promising lead-halide perovskites, are challenging due to the large number of atoms and lack of symmetries to exploit. Here, focusing on…

Materials Science · Physics 2022-10-05 Giulia Biffi , Yeongsu Cho , Roman Krahne , Timothy C. Berkelbach

We report on the excitation energy dependence of the inner ring in the exciton emission pattern. The contrast of the inner ring is found to decrease with lowering excitation energy. Excitation by light tuned to the direct exciton resonance…

Mesoscale and Nanoscale Physics · Physics 2012-05-03 Y. Y. Kuznetsova , J. R. Leonard , L. V. Butov , J. Wilkes , E. A. Muljarov , K. L. Campman , A. C. Gossard

Excitonic complexes in type-II quantum-ring heterostructures may be considered as artificial atoms due to the confinement of only one charge-carrier type in an artificial nucleus. Binding energies of excitons, trions, and biexcitons in…

Mesoscale and Nanoscale Physics · Physics 2019-03-08 David Thomas , Ryan Hunt , Neil Drummond , Manus Hayne

Using the exact propagators in a constant magnetic field, the neutrino self-energy has been calculated to all orders in the field strength $B$ within the minimal extension of the Weinberg-Salam model with massive Dirac neutrinos. A neutrino…

High Energy Physics - Phenomenology · Physics 2020-11-03 Andrea Erdas , Zachary Metzler

Quantum Stark effect in semiconductor nanocrystals is theoretically investigated, using the effective mass formalism within a $4\times 4$ Baldereschi-Lipari Hamiltonian model for the hole states. General expressions are reported for the…

Materials Science · Physics 2009-11-10 Eduardo Ariel Menendez Proupin , Carlos Trallero Giner

A theory of polaritonic states is developed for a nanostructure with a wide quantum well stressed perpendicular to the growth axis of the heterostructure. The role of the $K$-linear terms appearing in the exciton Hamiltonian under the…

Mesoscale and Nanoscale Physics · Physics 2014-08-20 D. K. Loginov , A. V. Trifonov , I. V. Ignatiev

Several new and interesting aspects of neutrino oscillations in a magnetic field are considered: 1) We develop a standard usually used approach to the neutrino spin oscillations in the neutrino mass basis and obtain the effective neutrino…

High Energy Physics - Phenomenology · Physics 2015-06-18 Alexander Dmitriev , Riccardo Fabbricatore , Alexander Studenikin

We investigate matter effects on highly relativistic neutrinos. The self-energy of neutrinos is determined in an electron or neutrino background taking into account resonance and finite width effects of the gauge bosons. We find minor…

High Energy Physics - Phenomenology · Physics 2009-11-11 Thomas Konstandin , Tommy Ohlsson

We consider a nanosystem connected to measurement probes via leads. When a magnetic flux is varied through a ring attached to one lead at a distance Lc from the nanosystem, the effective nanosystem transmission |ts|^2 exhibits Aharonov-Bohm…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Axel Freyn , Jean-Louis Pichard

The effective Hamiltonian describing the motion of an exciton in an external non-homogeneous magnetic field is derived. The magnetic field plays the role of an effective potential for the exciton motion, results into an increment of the…

Condensed Matter · Physics 2009-10-31 J. A. K. Freire , A. Matulis , F. M. Peeters , V. N. Freire , G. A. Farias

A novel magnetic interference effect is proposed for a neutral, but polarizable exciton in a quantum ring with a finite width. The magnetic interference effect originates from the nonzero dipole moment in the exciton. The ground state of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 S. E. Ulloa , A. O. Govorov , A. V. Kalameitsev , R. Warburton , K. Karrai

The scaling of exciton binding energy in semiconductor quantum wires is investigated theoretically through a non-variational, fully three-dimensional approach for a wide set of realistic state-of-the-art structures. We find that in the…

Condensed Matter · Physics 2009-10-30 F. Rossi , G. Goldoni , E. Molinari

Exciton effects are studied in single-wall boron-nitride (BN) nanotubes. Linear absorption spectra are calculated with changing the chiral index of the zigzag nanotubes. We consider the extended Hubbard model with atomic energies at the…

Materials Science · Physics 2009-07-07 Kikuo Harigaya

This research delves into the critical effects of magnetic interactions in low-dimensional systems, offering invaluable insights that deepen our comprehension of magnetic behavior at the nanoscale. By implementing this innovative approach,…

Mesoscale and Nanoscale Physics · Physics 2025-04-15 José Holanda

The effect of eccentricity distortions of core-multishell quantum wires on their electron, hole and exciton states is theoretically investigated. Within the effective mass approximation, the Schrodinger equation is numerically solved for…

Mesoscale and Nanoscale Physics · Physics 2014-03-28 Rair Macedo , J. Costa e Silva , Andrey Chaves , G. A. Farias , R. Ferreira