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Related papers: Discrete vs. continuous in the semiclassical limit

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We consider discrete Schr\"odinger operators with periodic potentials on periodic graphs perturbed by guided non-positive potentials, which are periodic in some directions and finitely supported in other ones. The spectrum of the…

Spectral Theory · Mathematics 2017-05-16 Evgeny Korotyaev , Natalia Saburova

In this paper we continue the study (initiated in arXiv:2003.13584) of the semiclassical behavior of the scattering data of a non-self-adjoint Dirac operator with a real, positive, fairly smooth but not necessarily analytic potential…

Mathematical Physics · Physics 2021-06-15 Nicholas Hatzizisis , Spyridon Kamvissis

We consider a family of multi-dimensional Schr\"odinger operators $-\Delta+t V$ with a real $t$. The potential $V$ in our model decays at infinity in a special way, so that it satisfies a certain integral condition. We prove that the…

Mathematical Physics · Physics 2012-03-20 Oleg Safronov

We consider discrete one-dimensional Schroedinger operators whose potentials decay asymptotically like an inverse square. In the super-critical case, where there are infinitely many discrete eigenvalues, we compute precise asymptotics of…

Spectral Theory · Mathematics 2015-09-29 David Damanik , Gerald Teschl

For Schr\"odinger operator $H=-\Delta+ V({\mathbf x})\cdot$, acting in the space $L_2(\mathbb R^d)\,(d\ge 3)$, necessary and sufficient conditions for semi-boundedness and discreteness of its spectrum.are obtained without assumption that…

Spectral Theory · Mathematics 2023-10-31 Leonid Zelenko

We consider a semi-classical Schrodinger operator with a degenerate potential V(x,y) =f(x) g(y) . g is assumed to be a homogeneous positive function of m variables and f is a strictly positive function of n variables, with a strict minimum.…

Mathematical Physics · Physics 2008-12-17 Abderemane Morame , Francoise Truc

We revisit the problem of semiclassical spectral asymptotics for a pure magnetic Schr\"odinger operator on a two-dimensional Riemannian manifold. We suppose that the minimal value $b_0$ of the intensity of the magnetic field is strictly…

Spectral Theory · Mathematics 2013-12-20 Bernard Helffer , Yuri A. Kordyukov

We consider Schr\"odinger operators in $\ell^2(\mathbb{Z})$ whose potentials are given by independent (not necessarily identically distributed) random variables. We ask whether it is true that almost surely its spectrum contains an…

Spectral Theory · Mathematics 2021-12-07 David Damanik , Anton Gorodetski

We prove that the spectrum of a limit-periodic Schr\"odinger operator is homogeneous in the sense of Carleson whenever the potential obeys the Pastur--Tkachenko condition. This implies that a dense set of limit-periodic Schr\"odinger…

Spectral Theory · Mathematics 2015-07-09 Jake Fillman , Milivoje Lukic

We consider a class of unbounded quasiperiodic Schr\"odinger-type operators on $\ell^2(\mathbb Z^d)$ with monotone potentials (akin to the Maryland model) and show that the Rayleigh--Schr\"odinger perturbation series for these operators…

Spectral Theory · Mathematics 2022-06-01 Ilya Kachkovskiy , Leonid Parnovski , Roman Shterenberg

We consider a periodic magnetic Schr\"odinger operator $H^h$, depending on the semiclassical parameter $h>0$, on a noncompact Riemannian manifold $M$ such that $H^1(M, {\mathbb R})=0$ endowed with a properly discontinuous cocompact…

Spectral Theory · Mathematics 2008-12-24 B. Helffer , Y. A. Kordyukov

We make a spectral analysis of discrete Schroedinger operators on the half-line, subject to complex Robin-type boundary couplings and complex-valued potentials. First, optimal spectral enclosures are obtained for summable potentials.…

Spectral Theory · Mathematics 2023-04-14 David Krejcirik , Ari Laptev , Frantisek Stampach

In this article we describe the semi-classical spectrum of a Schrodinger operator on $\mathbb{R}$ with a double well potential. We study the shape of spectrum around the local maximum of the potential. In the classification of singularities…

Spectral Theory · Mathematics 2009-12-18 Olivier Lablée

The two-dimensional Schroedinger operator with a uniform magnetic field and a periodic zero-range potential is considered. For weak magnetic fields we reduce the spectral problem to the semiclassical analysis of one-dimensional Harper-like…

Mathematical Physics · Physics 2009-05-24 Bernard Helffer , Konstantin Pankrashkin

The semi-classical regime of standing wave solutions of a Schr\"odinger equation in presence of non-constant electric and magnetic potentials is studied in the case of non-local nonlinearities of Hartree type. It is show that there exists a…

Analysis of PDEs · Mathematics 2009-11-13 Silvia Cingolani , Simone Secchi , Marco Squassina

Consider the semiclassical limit, as the Planck constant $\hbar\ri 0$, of bound states of a quantum particle in a one-dimensional potential well. We justify the semiclassical asymptotics of eigenfunctions and recover the Bohr-Sommerfeld…

Spectral Theory · Mathematics 2010-09-08 D. R. Yafaev

We consider the Schr\"odinger operator $H = -\Delta + V$ in a layer or in a $d$-dimensional cylinder. The potential $V$ is assumed to be periodic with respect to some lattice. We establish the absolute continuity of $H$, assuming $V \in…

Spectral Theory · Mathematics 2010-11-08 Nikolay Filonov , Ilya Kachkovskiy

For a large class of semiclassical pseudodifferential operators, including Schr\"odinger operators, $ P (h) = -h^2 \Delta_g + V (x) $, on compact Riemannian manifolds, we give logarithmic lower bounds on the mass of eigenfunctions outside…

Spectral Theory · Mathematics 2009-08-18 Hans Christianson

We prove three results giving sufficient and/or necessary conditions for discreteness of the spectrum of Schr\"odinger operators with non-negative matrix-valued potentials, i.e., operators acting on $\psi\in L^2(\mathbb{R}^n,\mathbb{C}^d)$…

Spectral Theory · Mathematics 2015-02-14 Gian Maria Dall'Ara

We prove a quantitative unique continuation principle for infinite dimensional spectral subspaces of Schr\"odinger operators. Let $\Lambda_L = (-L/2,L/2)^d$ and $H_L = -\Delta_L + V_L$ be a Schr\"odinger operator on $L^2 (\Lambda_L)$ with a…

Analysis of PDEs · Mathematics 2017-09-28 Matthias Täufer , Martin Tautenhahn
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