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Related papers: Quantum fluctuations stabilize Skyrmion textures

200 papers

We derive effective-mass electron Hamiltonian for a N\'eel antiferromagnet in the presence of a smooth texture of the staggered magnetization. For certain locations of electron band extrema, the texture produces a peculiar and anomalously…

Strongly Correlated Electrons · Physics 2023-01-16 Naïmo Davier , Revaz Ramazashvili

Magnetic skyrmions are swirling spin textures with topologically protected noncoplanarity. Recently, skyrmions with the topological number of unity have been extensively studied in both experiment and theory. We here show that a skyrmion…

Strongly Correlated Electrons · Physics 2018-10-24 Ryo Ozawa , Satoru Hayami , Yukitoshi Motome

We study the effects of light-cone fluctuations on the renormalized zero-point energy associated with a free massless scalar field in the presence of boundaries. In order to simulate light-cone fluctuations we introduce a space-time…

High Energy Physics - Theory · Physics 2014-01-31 E. Arias , C. H. G. Bessa , J. G. Dueñas , G. Menezes , N. F. Svaiter

One of the most intriguing manifestations of quantum zero-point fluctuations are the van der Waals and Casimir forces, often associated with vacuum fluctuations of the electromagnetic field. Here we study generalized fluctuation potentials…

Quantum Physics · Physics 2018-05-01 Ephraim Shahmoon , Ulf Leonhardt

We calculate the Casimir energy of a massless scalar field in a cavity formed by nearby parallel plates orbiting a rotating spherical body surrounded by quintessence, investigating the influence of the gravitational field on that energy, at…

High Energy Physics - Theory · Physics 2016-12-21 V. B. Bezerra , M. S. Cunha , L. F. F. Freitas , C. R. Muniz

We summarize several aspects of recent work on quantum stress tensor fluctuations and their role in driving fluctuations of the gravitational field. The role of correlations and anticorrelations is emphasized. We begin with a review of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. H. Ford , Chun-Hsien Wu

We study the stability and energetics associated to skyrmions appear- ing as excitations on curved surfaces. Using a continuum model we show that the presence of cylindrically radial and azimuthal fields destabilizes the skyrmions that…

Mesoscale and Nanoscale Physics · Physics 2015-09-03 V. L. Carvalho-Santos , R. G. Elias , D. Altbir , J. M. Fonseca

We consider and review the emergence of singular energy densities and field fluctuations at sharp boundaries or point-like field sources in the vacuum. The presence of singular energy densities of a field may be relevant from a conceptual…

We theoretically investigate field-induced switching of magnetic topology in a nanodisk-shaped sample of noncentrosymmetric dipolar magnet in which the Dzyaloshinskii-Moriya interaction that stabilizes an antiskyrmion with $N_{\rm sk}$=+1…

Mesoscale and Nanoscale Physics · Physics 2025-09-15 Tatsuki Muto , Masahito Mochizuki

The elementary excitations of skyrmion crystals experience both emergent magnetic fields and anharmonic interactions brought about by the topologically nontrivial noncollinear texture. The resulting flat bands cause strong spontaneous…

Strongly Correlated Electrons · Physics 2020-09-30 Alexander Mook , Jelena Klinovaja , Daniel Loss

We study the effects of quantum fluctuations and the excitation spectrum for the antiferromagnetic Heisenberg model on a two-dimensional quasicrystal, by numerically solving linear spin-wave theory on finite approximants of the octagonal…

Strongly Correlated Electrons · Physics 2009-11-10 Stefan Wessel , Igor Milat

We study a square-lattice spin-half Heisenberg model where frustration is introduced by competing nearest-neighbor bonds of different signs. We discuss the influence of quantum fluctuations on the nature of the zero-temperature phase…

Strongly Correlated Electrons · Physics 2009-11-07 Sven E. Krüger , Johannes Richter

By introducing biquadratic together with usual bilinear ferromagnetic nearest neighbor exchange interaction in a square lattice, we find that the energy of the spin-wave mode is minimized at a finite wavevector for a vanishingly small…

Mesoscale and Nanoscale Physics · Physics 2021-06-22 Sandip Bera , Sudhansu S. Mandal

A noncommutative complex scalar field, satisfying the deformed canonical commutation relations proposed by Carmona et al. [27]-[31], is constructed. Using these noncommutative deformed canonical commutation relations, a model describing the…

High Energy Physics - Theory · Physics 2012-06-19 Farid Khelili

The Casimir effect, reflecting quantum vacuum fluctuations in the electromagnetic field in a region with material boundaries, has been studied both theoretically and experimentally since 1948. The forces between dielectric and metallic…

Quantum Physics · Physics 2009-11-13 Iver Brevik , Simen A. Ellingsen , Kimball A. Milton

Electrons moving through a noncoplanar magnetic texture acquire a Berry phase, which can be described as an effective magnetic field. This effect is known as the topological Hall effect and has been observed in topological spin textures.…

Mesoscale and Nanoscale Physics · Physics 2022-10-21 Tan Dao , Sergey S. Pershoguba , Jiadong Zang

We investigate the impact of the local spin texture on the differential conductance by scanning tunneling microscopy. In the focus is the previously found non-collinear magnetoresistance, which originates from spin mixing effects upon…

Materials Science · Physics 2017-04-05 André Kubetzka , Christian Hanneken , Roland Wiesendanger , Kirsten von Bergmann

We develop a quantum theory of magnetic skyrmions and antiskyrmions in a spin-1/2 Heisenberg magnet with frustrating next-nearest neighbor interactions. Using exact diagonalization we show numerically that a quantum skyrmion exists as a…

Strongly Correlated Electrons · Physics 2020-01-01 Vivek Lohani , Ciarán Hickey , Jan Masell , Achim Rosch

We present a microscopic theory of skyrmions in the monolayer quantum Hall ferromagnet. It is a peculiar feature of the system that the number density and the spin density are entangled intrinsically as dictated by the W$%_{\infty}$…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 G. Tsitsishvili , Z. F. Ezawa

The Jordan-Wigner transformation connects spin operators in one-dimensional spin systems and fermionic operators. In this work, we elucidate the relationship between the finite-size corrections in the spin representation and the fermionic…

Statistical Mechanics · Physics 2026-01-28 Katsumasa Nakayama , Kei Suzuki