English
Related papers

Related papers: An ab initio effective Hamiltonian for magnetism i…

200 papers

We identify the low energy effective Hamiltonian that is expected to describe the low temperature properties of the frustrated magnet $\mathrm{Ca}_{10}\mathrm{Cr}_{7}\mathrm{O}_{28}$. Motivated by the fact that this effective Hamiltonian…

Strongly Correlated Electrons · Physics 2018-03-07 Sounak Biswas , Kedar Damle

It is demonstrated that thermally induced longitudinal spin fluctuations (LSF) play an important role in itinerant Co$_3$Mn$_2$Ge at an elevated temperature. The effect of LSF is taken into account during {\it ab initio} calculations via a…

Materials Science · Physics 2022-06-01 Erna K. Delczeg-Czirjak , O. Eriksson , A. V. Ruban

Using the Hamiltonian formulation of Composite Fermions developed recently, the temperature dependence of the spin polarization is computed for the translationally invariant fractional quantum Hall states at $\nu=1/3$ and $\nu=2/5$ in two…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Ganpathy Murthy

We develop a self-consistent relativistic disordered local moment (RDLM) scheme aimed at describing finite temperature magnetism of itinerant metals from first principles. Our implementation in terms of the Korringa--Kohn--Rostoker multiple…

Materials Science · Physics 2015-06-19 A. Deák , E. Simon , L. Balogh , L. Szunyogh , M. dos Santos Dias , J. B. Staunton

Spin fluctuations have a substantial influence on the electron and lattice behaviors in magnetic materials, which, however, is difficult to be tracked properly by prevalent first-principles methods. We propose a versatile self-adaptive…

Materials Science · Physics 2023-02-14 Zefeng Cai , Ke Wang , Yong Xu , Su-Huai Wei , Ben Xu

It is generally accepted that the effective magnetic field acting on a magnetic moment is given by the gradient of the energy with respect to the magnetization. However, in ab initio spin dynamics within the adiabatic approximation, the…

We propose a first-principles formulism for system with spin fluctuations and apply it to the ordered Fe3Pt to uncover the Invar anomalies, including negative thermal expansion and spontaneous magnetization. The theory has coherently…

Materials Science · Physics 2014-02-25 Y. Wang , S. L. Shang , H. Zhang , L. -Q. Chen , Z. -K. Liu

We describe an ab initio theory of finite temperature magnetism in strongly-correlated electron systems. The formalism is based on spin density functional theory, with a self-interaction corrected local spin density approximation…

Strongly Correlated Electrons · Physics 2009-11-13 I. D. Hughes , M. Daene , A. Ernst , W. Hergert , M. Lueders , J. B. Staunton , Z. Szotek , W. M. Temmerman

Noncollinear magnetic moments in antiferromagnets (AFM) lead to a complex behavior of electrical transport, even to a decreasing resistivity due to an increasing temperature. Proper treatment of such phenomena is required for understanding…

Materials Science · Physics 2020-06-19 David Wagenknecht , Karel Výborný , Karel Carva , Ilja Turek

The ferrimagnetic insulator Mn3Si2Te6, which features a Curie temperature Tc at 78 K and a delicate yet consequential magnetic frustration, exhibits colossal magnetoresistance (CMR) when the magnetic field is applied along the magnetic hard…

Strongly Correlated Electrons · Physics 2022-11-02 Feng Ye , Masaaki Matsuda , Zachary Morgan , Todd Sherline , Yifei Ni , Hengdi Zhao , G. Cao

We explore the derivation of interatomic exchange interactions in ferromagnets within density-functional theory (DFT) and the mapping of DFT results onto a spin Hamiltonian. We delve into the problem of systems comprising atoms with strong…

Materials Science · Physics 2013-10-10 Marjana Lezaic , Phivos Mavropoulos , Gustav Bihlmayer , Stefan Blügel

We investigate the contributions of finite-temperature magnetic fluctuations to the thermodynamic properties of bcc Fe as a function of pressure. First, we apply a tight-binding total-energy model parameterized to first-principles…

Materials Science · Physics 2010-07-21 Xianwei Sha* , R. E. Cohen

Magnetic properties of more than twenty Cantor alloy samples of varying composition were investigated over a temperature range of 5 K to 300 K and in fields of up to 70 kOe using magnetometry and muon spin relaxation. Two transitions are…

Magnetic properties of Fe, Co, and Ni at finite temperatures have been investigated on the basis of the first-principles dynamical CPA (Coherent Potential Approximation) combined with the LDA (Local Density Approximation) + $U$ Hamiltonian…

Strongly Correlated Electrons · Physics 2015-05-27 Yoshiro Kakehashi , M. Atiqur R. Patoary

The recent observations of ferromagnetic order in several two-dimensional (2D) materials have generated an enormous interest in the physical mechanisms underlying 2D magnetism. In the present prospective article we show that Density…

Materials Science · Physics 2020-02-18 Thomas Olsen

Atomistic spin model simulations are immensely useful in determining temperature dependent magnetic prop- erties, but are known to give the incorrect dependence of the magnetization on temperature compared to exper- iment owing to their…

Mesoscale and Nanoscale Physics · Physics 2015-05-12 R. F. L. Evans , U. Atxitia , R. W. Chantrell

Vacancy is one of the most frequent defects in metals. We study the impacts of magnetism on vacancy formation properties in fcc Ni, and in bcc and fcc Fe, via density functional theory (DFT) and effective interaction models combined with…

Materials Science · Physics 2023-11-14 Kangming Li , Chu-Chun Fu , Anton Schneider

Inelastic neutron scattering technique is employed to investigate the paramagnetic spin dynamics in a single crystalline sample of the magnetocaloric compound MnFe$_4$Si$_3$. In the investigated temperature range, 1.033$\times T_{C}$ to…

Materials Science · Physics 2025-02-21 N. Biniskos , K. Schmalzl , J. Persson , S. Raymond

We present an ab-initio-based effective interaction model (EIM) for the study of magnetism, thermodynamics, and their interplay in body-centered cubic Fe-Co alloys, with Co content from 0 to 70%. The model includes explicitly both spin and…

Materials Science · Physics 2020-01-16 Van-Truong Tran , Chu-Chun Fu , Anton Schneider

Atomic-scale computational modeling of technologically relevant permanent magnetic materials faces two key challenges. First, a material's magnetic properties depend sensitively on temperature, so the calculations must account for thermally…

Materials Science · Physics 2018-06-15 Christopher E. Patrick , Julie B. Staunton
‹ Prev 1 2 3 10 Next ›