Related papers: Finite temperature magnetic interactions from firs…
We investigate the classical antiferromagnetic Heisenberg model on the triangular lattice with up to third-nearest neighbor exchange couplings using the Nematic Bond Theory. This approach allows us to compute the free energy and the neutron…
The influence of finite temperatures and pairing correlations on the ground state properties of multi $\Lambda$- Ca, Sn and Pb hypernuclei is explored using finite temperature Hartree Fock Bogoliubov approach and contact pairing…
The high-temperature ferromagnet MnBi continues to receive attention as a candidate to replace rare-earth-containing permanent magnets in applications above room temperature. This is due to a high Curie temperature, large magnetic moments,…
The temperature dependence of magneto current in the spin spin valve transistor system is theoretically explored based on phenomenological model. We find that the collector current strongly depends on the relative orientation of magnetic…
We introduce the Hamiltonian to describe narrow band electrons. The physics of driving forces towards ferromagnetism is re-examined. Using different approximations it has been shown that the magnetic moments created by inter-site…
Characteristic temperatures in ferromagnetic - antiferromagnetic exchange biased systems are analyzed. In addition to usual blocking temperature of exchange bias $T_{B}$, and the N\'{e}el temperature of an antiferromagnet $T_{N}$, the…
It is desirable to relate entanglement of many-body systems to measurable observables. In systems with a conserved charge, it was recently shown that the number entanglement entropy (NEE) - i.e. the entropy change due to an unselective…
The exchange-driven contribution to the magnetoelectric susceptibility $\hat\alpha$ is formulated using a microscopic model Hamiltonian coupling the spin degrees of freedom to lattice displacements and electric field, which may be…
Reports of emergent conductivity, superconductivity, and magnetism at oxide interfaces have helped to fuel intense interest in their rich physics and technological potential. Here we employ magnetic force microscopy to search for…
Epitaxial superlattices of ferromagnetic/paramagnetic La$_{0.67}$Sr$_{0.33}$MnO$_3$/SrIrO$_3$ materials have been prepared on SrTiO$_3$ (100) substrate using pulse laser deposition technique. An unexpected onset of interface magnetic…
Element specific ultrafast demagnetization was studied in Fe$_{1-x}$Ni$_{x}$ alloys, covering the concentration range between $0.1<x<0.9$. For all compositions, we observe a delay in the onset of Ni demagnetization relative to the Fe…
A sensor for thermal and thermodynamic measurements of small magnetic systems have been designed and built. It is based on a 5μm-thick suspended polymer membrane, which has a very low heat capacity (≈ 10-6 J/K at nitrogen…
We derive an effective field theory model for magnetic topological insulators and predict that a magnetic electronic gap persists on the surface for temperatures above the ordering temperature of the bulk. Our analysis also applies to…
We study pairing correlations in ultrasmall superconductor in the nanoscopic limit by means of a toy model where electrons are confined in a single, multiply degenerate energy level. We solve the model exactly to investigate the temperature…
We present a new method of calculating the rate of neutrino-electron interactions in a strong magnetic field based on finite temperature field theory. Using this method, in which the effect of the magnetic field on the electron states is…
We report magnetic susceptibility $\chi(T)$ measurements on oxygen-isotope exchanged La$_{1-x}$Ca$_{x}$MnO$_{3+y}$ up to 700 K. The $1/\chi(T)$ data show that the ferromagnetic exchange-energy $J$ depends strongly on the oxygen-isotope…
A few $4d$ and $5d$ transition metal compounds with various electron fillings were recently found to exhibit magnetic susceptibilities $\chi$ and magnetic moments that deviate from the well-established Kotani model. This model has been…
The MnAs compound shows a first-order transition at T$_C\approx42$ C, and a second-order transition at T$_t\approx120$ C. The first-order transition, with structural (hexagonal-orthorhombic), magnetic (FM-PM) and electrical conductivity…
The temperature dependence of the optical and magnetic properties of CuO were examined by means of hybrid density functional theory calculations. Our work shows that the spin exchange interactions in CuO are neither fully one-dimensional…
Here we investigate the temperature evolution of the structural parameters of a potential magnetoelectric material, MnTiO$_{3}$. The experimental results reveal interesting temperature dependence of the $c/a$ ratio and the Mn-O bonds which…