Related papers: Migdal-Eliashberg theory as a classical spin chain
Different classical theories are commonly applied in various branches of physics to describe the relativistic dynamics of electrons by coupled equations for the orbital motion and spin precession. Exemplarily, we benchmark the Frenkel model…
The rapidly rising fields of spintronics and quantum information science have led to a strong interest in developing the ability to coherently manipulate electron spins. Electron spin resonance (ESR) is a powerful technique to manipulate…
The phenomenology of LiFeAs superconductor can be explained in the framework of a four-band s$\pm$-wave Eliashberg theory. We have examined the experimental data available in literature and we have found out that it is possible to reproduce…
We analyse the ground-state energy and correlation energy of the Heisenberg model as a function of spin, both in the ferromagnetic and in the antiferromagnetic case, and in one, two and three dimensions. First, we present a comparative…
An equation proposed by Levy, Perdew and Sahni in 1984 [PRA 30, 2745 (1984)] is an orbital--free formulation of density functional theory. However, this equation describes a bosonic system. Here, we analyze on a very fundamental level, how…
We investigate the interplay between mechanical forces and the internal-state dynamics of a chain of Rydberg atoms trapped in tweezer arrays under the facilitation constraint. Dipole interactions between Rydberg atoms couple electronic…
We investigate interactions and ultracold collisions of high-spin but spherical atoms with closed-shell atoms, focussing on the example of Cr with Yb. Such a combination has only one potential energy curve but gives rise to a substantial…
We put forward a new approach based on Green's function formalism to evaluate precisely persistent charge and spin currents in an Aharonov-Bohm ring subjected to Rashba and Dresselhaus spin-orbit interactions. Unlike conventional methods…
Correlation functions of ferromagnetic spin systems satisfying a Lee-Yang property are studied. It is shown that, for classical systems in a non-vanishing uniform external magnetic field $h$, the connected correlation functions decay…
Spontaneous magnon decays in an $S=\frac{1}{2}$ Heisenberg antiferromagnet on the equilateral triangular prism are investigated in terms of modified magnon Green's functions. In one dimension, the so-called infrared divergence prevents us…
We study the long-time decay of fourth-order electron spin correlation functions for an isolated singly charged semi-conductor quantum dot. The electron spin dynamics is governed by the applied external magnetic field as well as the…
We study the spin-Peierls transition in a Heisenberg spin chain coupled to optical bond-phonons. Quantum Monte Carlo results for systems with up to N=256 spins show unambiguously that the transition occurs only when the spin-phonon coupling…
We reassess the validity of Migdal-Eliashberg (ME) theory for coupled electron-phonon systems for large couplings $\lambda$. Although model calculations have found that ME theory breaks down for $\lambda\sim 0.5$, it is routinely applied…
Modifications of spin-splitting dispersion relations and density of states for electrons in non-symmetric heterostructures under in-plane magnetic field are studied within the envelope function formalism. Spin-orbit interactions, caused by…
We theoretically and numerically investigate spin waves that occur in systems of classical magnetic dipoles that are arranged at the vertices of a regular polygon and interact solely via their magnetic fields. There are certain limiting…
We study gapless quantum spin chains with spin 1/2 and 1: the Fredkin and Motzkin models. Their entangled groundstates are known exactly but not their excitation spectra. We first express the groundstates in the continuum which allows for…
We analyze new spin effects in current-carrying state of superconductor-2D electron gas-superconductor (S-2DEG-S) device with spin-polarized nuclei in 2DEG region. The hyperfine interaction of 2D electrons with nuclear spins, described by…
By exploiting density-matrix renormalization group techniques, we investigate the dynamical spin structure factor of a spin-1/2 Heisenberg chain with ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange…
We present a spin-rotation-invariant Green-function theory for the dynamic spin susceptibility in the spin-1/2 antiferromagnetic Heisenberg model on a stacked honeycomb lattice. Employing a generalized mean-field approximation for arbitrary…
Spin-orbit coupling in systems with broken inversion symmetry gives rise to the Edelstein effect, which is the spin polarization induced by an electric field or current, and the inverse-Edelstein effect (also known as the spin-galvanic…