Related papers: Quantum Spin Effect and Short-Range Order above th…
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…
This study aims to unravel the mechanism of colossal magnetoresistance (CMR) observed in n-type HgCr$_2$Se$_4$, in which low-density conduction electrons are exchange-coupled to a three-dimensional Heisenberg ferromagnet with a Curie…
Three-dimensional magnetic ordering transitions are studied theoretically in strongly anisotropic quantum magnets. An external magnetic field can drive quasi-one-dimensional subsystems with a spin gap into a gapless regime, thus inducing…
We show that the low-temperature physics of molecular nanomagnets, contrary to the prevailing one-molecule picture, must be determined by the long-range magnetic ordering due to many-body dipolar interactions. The calculations here…
In this work we investigate quantum transport in Cu nanowires created by bringing macroscopic Cu wires into and out of contact under an applied magnetic field in air. Here we show that a 70 % magneto-conductance effect can be seen in a Cu…
We investigate cubic-in-spin effects for inspiralling compact objects binaries, both in the dynamics and the energy flux emitted in gravitational waves, at the leading post-Newtonian order. We use a Lagrangian formalism to implement…
A new topological excitation called skyrmion has been observed experimentally in chiral magnets without spatial inversion symmetry. The dynamics of a skyrmion is equivalent to an electron moving in a strong magnetic field. As a skyrmion…
This work is concerned with thermal quantum states of Hamiltonians on spin and fermionic lattice systems with short range interactions. We provide results leading to a local definition of temperature, thereby extending the notion of…
Within Takahashi's spin-wave theory we study finite size and temperature effects near the quantum critical point in the $J_{1}-J_{2}$ Heisenberg antiferromagnet defined on a strip ($L\times\infty$). In the continuum limit, the theory…
The Pair Approximation method is applied to studies of the bilayer and multilayer magnetic systems with simple cubic structure. The method allows to take into account quantum effects related with non-Ising couplings. The paper adopts the…
Atomistic spin dynamics (ASD) is a standard tool to model the magnetization dynamics of a variety of materials. The fundamental dynamical model underlying ASD is entirely classical. In this paper, we present two approaches to effectively…
Spin wave theory is a key ingredient in our comprehension of quantum spin systems, and is used successfully for understanding a wide range of magnetic phenomena, including magnon condensation and stability of patterns in dipolar systems.…
The thermodynamic properties (magnetization, magnetic susceptibility, transverse and longitudinal correlation lengths, specific heat) of one- and two-dimensional ferromagnets with arbitrary spin S in a magnetic field are investigated by a…
We study the effect of spin-orbit interaction and in-plane effective magnetic field on the conductance of a quasi-one-dimensional ballistic electron system. The effective magnetic field includes the externally applied field, as well as the…
We use atomistic stochastic Landau-Lifshitz-Slonczewski simulations to study the interaction between large thermal fluctuations and spin transfer torques in the magnetic layers of spin valves. At temperatures near the Curie temperature…
We estimate, using high-temperature series expansions, the transition temperatures of the spin 1/2, 1 and 3/2 Heisenberg ferromagnet and antiferromagnet in 3-dimensions. The manner in which the difference between Curie and Neel temperatures…
We take a two-step theoretical approach to study magnetism of rare earth quasicrystals by considering Ising spins on quasiperiodic tilings, coupled via RKKY interactions. First, we compute RKKY interactions from a tight-binding Hamiltonian…
Condensed matter physics plays a crucial role in modern scientific research and technological advancements, providing insights into the behavior of materials and their fundamental properties. Understanding complex phenomena and systems in…
The thermodynamics of the quantum Heisenberg antiferromagnet on a square lattice is revisited through a linearized spin-wave theory which is well defined at any finite temperature. We re-examine in details the temperature dependence of the…
The field-driven reorientation transition of an anisotropic ferromagnetic monolayer is studied within the context of a finite-temperature Green's function theory. The equilibrium state and the field dependence of the magnon energy gap $E_0$…