English
Related papers

Related papers: Quantum Theory of Helimagnetic Thin Films

200 papers

Magnetic properties of fcc structured ferromagnetic films with the number of spin layers up to seventy was described using third order perturbed Heisenberg Hamiltonian. The variation of magnetic easy direction, magnetic energies in easy and…

Materials Science · Physics 2017-12-08 P. Samarasekara , N. U. S. Yapa , C. A. N. Fernando

We study quantum spin-1/2 Heisenberg ferromagnetic chains with dilute, random antiferromagnetic impurity bonds with modified spin-wave theory. By describing thermal excitations in the language of spin waves, we successfully observe a…

Disordered Systems and Neural Networks · Physics 2009-11-07 Xin Wan , Kun Yang , Chenggang Zhou , R. N. Bhatt

We investigate the magnetic properties of a range of low-dimensional ferromagnets using a combination of first-principles calculations and atomistic spin dynamics simulations. This approach allows us to evaluate the ground state and finite…

Materials Science · Physics 2016-11-26 Lars Bergqvist , Andrea Taroni , Anders Bergman , Corina Etz , Olle Eriksson

The ferrimagnetic spin-1/2 chain composed of alternating Ising and Heisenberg spins in an arbitrarily oriented magnetic field is exactly solved using the spin-rotation transformation and the transfer-matrix method. It is shown that the…

Statistical Mechanics · Physics 2012-12-27 J. Strecka , M. Hagiwara , Y. Han , T. Kida , Z. Honda , M. Ikeda

We develop a simple and unbiased numerical method to obtain the uniform susceptibility of quantum many body systems. When a Hamiltonian is spatially deformed by multiplying it with a sine square function that smoothly decreases from the…

Strongly Correlated Electrons · Physics 2018-11-07 Chisa Hotta , Kenichi Asano

In this paper we present a mathematical analysis of thin film flow and heat transfer to a laminar liquid film from a horizontal stretching sheet. The flow of thin liquid film and subsequent heat transfer from the stretching surface is…

Fluid Dynamics · Physics 2016-03-14 Prashant G Metri , Jagdish Tawade , M Subhash Abel

In order to model a spiral spin state in a thin film, we study a classical Heisenberg model with open boundary conditions. With magnetic field applied in the plane of the film, the spin state becomes ferromagnetic above a critical field…

Materials Science · Physics 2017-08-02 Randy S. Fishman , Satoshi Okamoto

The quantum nanomagnets show interesting site-dependent magnetic properties as a function of the temperature and the external magnetic field. In the paper we present the results of calculations for a finite quantum spin ladder with two…

Mesoscale and Nanoscale Physics · Physics 2018-09-11 K. Szałowski , P. Kowalewska

We have investigated the spin fluctuations in the langasite compound Ba3NbFe3Si2O14 in both the ordered state and as a function of temperature. The low temperature magnetic structure is defined by a spiral phase characterized by magnetic…

Strongly Correlated Electrons · Physics 2015-05-19 C. Stock , L. C. Chapon , A. Schneidewind , Y. Su , P. G. Radaelli , D. F. McMorrow , A. Bombardi , N. Lee , S. -W. Cheong

We study a thermally induced spin flip of an electron spin located in a semiconductor quantum dot. This interesting effect arises from an intriguing interplay between the Zeeman coupling to an external magnetic field and the hyperfine…

Mesoscale and Nanoscale Physics · Physics 2015-08-05 Moritz Fuchs , Felix Krauß , Daniel Hetterich , Björn Trauzettel

We study the magnetic dynamics of magnetoelectric antiferromagnetic thin films, where an unconventional boundary ferromagnetism coexists with the bulk N\'{e}el phase below the N\'{e}el temperature. The spin exchange between the two order…

Mesoscale and Nanoscale Physics · Physics 2018-01-24 Ricardo Zarzuela , Se Kwon Kim , Yaroslav Tserkovnyak

The thermodynamics of low dimensional spin-1/2 Heisenberg ferromagnets (HFM) in an external magnetic field is investigated within a second-order two-time Green function formalism in the wide temperature and field range. A crucial point of…

Strongly Correlated Electrons · Physics 2009-11-13 T. N. Antsygina , M. I. Poltavskaya , I. I. Poltavsky , K. A. Chishko

We investigate classical Heisenberg spins on a conical surface. The energy and configuration of non-trivial spin distributions are obtained using a non-conventional method based on Einstein theory of gravity in lower dimensions.

Strongly Correlated Electrons · Physics 2007-05-23 Afranio Rodrigues Pereira

We perform a study on the evolution of helical quantum turbulence at different temperatures by solving numerically the Gross-Pitaevskii and the Stochastic Ginzburg-Landau equations, using up to $4096^3$ grid points with a pseudospectral…

Fluid Dynamics · Physics 2018-09-26 P. Clark di Leoni , P. D. Mininni , M. -E. Brachet

In thin topological insulator films, the top and bottom surfaces are coupled by tunneling, which restores backscattering and strongly affects screening. We calculate the dielectric function in the random phase approximation obtaining a…

Mesoscale and Nanoscale Physics · Physics 2014-05-19 Weizhe Edward Liu , Hong Liu , Dimitrie Culcer

Helical magnets are emerging as a novel class of materials for spintronics and sensor applications; however, research on their charge and spin transport properties in a thin film form is less explored. Herein, we report the temperature and…

Spin polarized scanning tunneling microscopy is used to directly image topological magnetic textures in thin films of MnGe, and to correlate the magnetism with structure probed at the atomic-scale. Our images indicate helical stripe…

A spin-wave theory of short-range order in the square lattice Heisenberg antiferromagnet is formulated. With growing temperature from T=0 a gapless mode is shown to arise simultaneously with opening a gap in the conventional spin-wave mode.…

Strongly Correlated Electrons · Physics 2009-10-31 A. Sherman , M. Schreiber

An important contribution to the thermoelectric and spin-caloric transport properties in magnetic materials at elevated temperatures is the formation of a spin-disordered state due to local moment fluctuations. This effect has not been…

Materials Science · Physics 2015-06-23 Roman Kováčik , Phivos Mavropoulos , Stefan Blügel

Monte Carlo simulations have been used to study phase transitions on coupled anisotropic ferro/antiferromagnetic (FM/AFM) films of classical Heisenberg spins. We consider films of different thicknesses, with fully compensated exchange…

Condensed Matter · Physics 2009-11-10 Shan-Ho Tsai , D. P. Landau , Thomas C. Schulthess