Zobrazeno 1 - 10
of 1 321
pro vyhledávání: '"Kachmar, A"'
Autor:
Helffer, Bernard, Kachmar, Ayman
We investigate a Hamiltonian with radial potential wells and an Aharonov-Bohm vector potential with two poles. Assuming that the potential wells are symmetric, we derive the semi-classical asymptotics of the splitting between the ground and second st
Externí odkaz:
http://arxiv.org/abs/2407.16524
Autor:
Kachmar, Ayman, Miranda, Germán
The magnetic Laplacian on a planar domain under a strong constant magnetic field has eigenvalues close to the Landau levels. We study the case when the domain is a disc and the spectrum consists of branches of eigenvalues of one dimensional operators
Externí odkaz:
http://arxiv.org/abs/2407.11241
Autor:
Fournais, Soeren, Kachmar, Ayman
For the magnetic Laplacian on a bounded planar domain, imposing Neumann boundary conditions produces eigenvalues below the lowest Landau level. If the domain has two boundary components and one imposes a Neumann condition on one component and a Diric
Externí odkaz:
http://arxiv.org/abs/2406.06411
We study the magnetic Laplacian in a two-dimensional exterior domain with Neumann boundary condition and uniform magnetic field. For the exterior of the disk we establish accurate asymptotics of the low-lying eigenvalues in the weak magnetic field li
Externí odkaz:
http://arxiv.org/abs/2405.18154
Autor:
Kachmar, Ayman, Sundqvist, Mikael
Starting from the Ginzburg--Landau model in a planar simply connected domain, with a local compactly supported applied magnetic field, we derive an effective model in the strong field limit, defined on a non-simply connected domain. The effective mod
Externí odkaz:
http://arxiv.org/abs/2405.09099
It is a well known fact that the geometry of a superconducting sample influences the distribution of the surface superconductivity for strong applied magnetic fields. For instance, the presence of corners induces geometric terms described through eff
Externí odkaz:
http://arxiv.org/abs/2403.11286
Autor:
Kachmar, Ayman, Lotoreichik, Vladimir
We obtain an upper bound on the lowest magnetic Neumann eigenvalue of a bounded, convex, smooth, planar domain with moderate intensity of the homogeneous magnetic field. This bound is given as a product of a purely geometric factor expressed in terms
Externí odkaz:
http://arxiv.org/abs/2312.06161
Autor:
Toufik Bouddine, Mohamed Reda Kachmar, Mourad Akdad, Aziz Bouymajane, Mohamed Ajebli, Ramzi A. Mothana, Abdullah R. Alanzi, Hassan Hajjaj, Farid Khallouki, Wim Reybroeck, Christof Van Poucke, Lhoussain Hajji
Publikováno v:
ACS Omega, Vol 9, Iss 45, Pp 44956-44973 (2024)
Externí odkaz:
https://doaj.org/article/f3ae3a06179646ccafdceb45a43bb207
We study the Pauli operator in a two-dimensional, connected domain with Neumann or Robin boundary condition. We prove a sharp lower bound on the number of negative eigenvalues reminiscent of the Aharonov-Casher formula. We apply this lower bound to o
Externí odkaz:
http://arxiv.org/abs/2307.16079
Motivated by the analysis of the tunneling effect for the magnetic Laplacian, we introduce an abstract framework for the spectral reduction of a self-adjoint operator to a hermitian matrix. We illustrate this framework by three applications, firstly
Externí odkaz:
http://arxiv.org/abs/2307.06712