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We consider eigenvalues of the Pauli operator in $\mathbb R^3$ embedded in the continuous spectrum. In our main result we prove the absence of such eigenvalues above a threshold which depends on the asymptotic behavior of the magnetic and…

Mathematical Physics · Physics 2023-12-11 Dirk Hundertmark , Hynek Kovarik

The spectral analysis of a non-Hermitian unbounded operator appearing in quantum physics is our main concern. The properties of such an operator are essentially different from those of Hermitian Hamiltonians, namely due to spectral…

Electron diffraction from nanogratings provides a platform for free-electron interferometry, yet controlled manipulation of electron spin in such geometries remains largely unexplored. In particular, the role of the self-generated magnetic…

Quantum Physics · Physics 2026-03-11 Sushanta Barman , Kuldeep Godara , Sudeep Bhattacharjee

Tensor-valued and matrix-valued measurements of different physical properties are increasingly available in material sciences and medical imaging applications. The eigenvalues and eigenvectors of such multivariate data provide novel and…

Methodology · Statistics 2017-07-24 Dario Gasbarra , Sinisa Pajevic , Peter J. Basser

We investigate transient radiation processes in the non-linear superradiance (SR) regime of the Doppler broadened Maxwell-Bloch equations when the velocity distribution is of total bandwidth greatly exceeding that of the transient process…

The distortion from massive MIMO (multiple-input--multiple-output) base stations with nonlinear amplifiers is studied and its radiation pattern is derived. The distortion is analyzed both in-band and out-of-band. By using an orthogonal…

Information Theory · Computer Science 2018-05-04 Christopher Mollén , Ulf Gustavsson , Thomas Eriksson , Erik G. Larsson

The largest eigenvalue of random tensors is an important feature of systems involving disorder, equivalent to the ground state energy of glassy systems or to the injective norm of quantum states. For symmetric Gaussian random tensors of…

High Energy Physics - Theory · Physics 2024-12-16 Nicolas Delporte , Naoki Sasakura

The open problem of calculating the limiting spectrum (or its Shannon transform) of increasingly large random Hermitian finite-band matrices is described. In general, these matrices include a finite number of non-zero diagonals around their…

Information Theory · Computer Science 2008-05-13 Oren Somekh , Osvalso Simeone , Benjamin M. Zaidel , H. Vincent Poor , Shlomo Shamai

W-band ({\nu} ca. 94 GHz) electron paramagnetic resonance (EPR) spectroscopy was used for a single-crystal study of a star-shaped Fe3Cr single-molecule magnet (SMM) with crystallographically imposed trigonal symmetry. The high resolution…

Mesoscale and Nanoscale Physics · Physics 2013-09-13 L. Sorace , M. -E. Boulon , P. Totaro , A. Cornia , J. Fernandes-Soares , R. Sessoli

This paper focuses on random projection operators when the subspace of projection is estimated. We derive non-asymptotic upper bounds on the error between the projection onto the estimated subspace and the projection onto the underlying…

Statistics Theory · Mathematics 2026-03-31 Luca Castelli

Gaussian cosmic microwave background skies are fully specified by the power spectrum. The conventional method of characterizing non-Gaussian skies is to evaluate higher order moments, the n-point functions and their Fourier transforms. We…

Astrophysics · Physics 2011-05-10 Pedro G. Ferreira , Joao Magueijo

Model-driven analysis of biophysical phenomena is gaining increased attention and utility for medical imaging applications. In magnetic resonance imaging (MRI), the availability of well-established models for describing the relations…

Medical Physics · Physics 2023-10-31 Dinor Nagar , Nikita Vladimirov , Christian T. Farrar , Or Perlman

Using extensive Brownian dynamics computer simulations, the long-time self-diffusion coefficient is calculated for Gaussian-core particles as a function of the number density. Both spherical and rod-like particles interacting via Gaussian…

Soft Condensed Matter · Physics 2012-07-17 H. H. Wensink , H. Löwen , M. Rex , C. N. Likos , S. van Teeffelen

We calculate the magnetic SANS cross section of dilute ensembles of uniformly magnetized and randomly-oriented Stoner-Wohlfarth particles using the Landau-Lifshitz equation. The focus of our study is on the angular anisotropy of the…

Materials Science · Physics 2022-10-18 Michael P. Adams , Evelyn Pratami-Sinaga , Andreas Michels

This article is concerned with uniqueness and stability issues for the inverse spectral problem of recovering the magnetic field and the electric potential in a Riemannian manifold from some asymptotic knowledge of the boundary spectral…

Analysis of PDEs · Mathematics 2018-10-30 Mourad Bellassoued , Mourad Choulli , Dos Santos Ferreira , Yavar Kian , Plamen Stefanov

In this contribution we analyze the spectral properties of some commonly used boundary integral operators in computational electromagnetics and of their discrete counterparts, highlighting peculiar features of their spectra. In particular,…

Computational Engineering, Finance, and Science · Computer Science 2024-07-15 V. Giunzioni , A. Merlini , F. P. Andriulli

In mathematical physics, the gradient operator with nonconstant coefficients encompasses various models, including Fourier's law for heat propagation and Fick's first law, that relates the diffusive flux to the gradient of the…

Functional Analysis · Mathematics 2024-08-23 Fabrizio Colombo , Francesco Mantovani , Peter Schlosser

Despite the tremendous progresses in wavefront control through or inside complex scattering media, several limitations prevent reaching practical feasibility for nonlinear imaging in biological tissues. While the optimization of nonlinear…

Optics · Physics 2016-12-06 Hilton B. de Aguiar , Sylvain Gigan , Sophie Brasselet

Real-valued band structures are foundational to analyzing periodic systems within the Hermitian description and have been experimentally well-established over recent decades. In contrast, non-Hermitian systems exhibit complex band…

Quantum Physics · Physics 2025-10-24 Jia-Xin Zhong , Jing Lin , Kai Chen , Jing Lu , Kun Ding , Yun Jing

We propose a novel framework for joint magnetic resonance image reconstruction and uncertainty quantification using under-sampled k-space measurements. The problem is formulated as a Bayesian linear inverse problem, where prior…

Image and Video Processing · Electrical Eng. & Systems 2026-03-17 Ahmed Karam Eldaly , Matteo Figini , Daniel C. Alexander