Heisenberg model

Part 2 book "Quantum optics for beginners" by author Zbigniew Ficek includes contents: Heisenberg equations of motion; dressed atom model; fokker– planck equation; quantum trajectory theory; interaction - free measurements; classical and quantum interference; atom– atom entanglement; classical and quantum lithography; laser model in the high; input– output theory; motion of atoms in a laser field.

171p muasambanhan09 16-03-2024 6 0   Download

Part 2 book "Classical and quantum statistical physics - Fundamentals and advanced topics" includes content: Magnetism in matter, the 2D ising model, the heisenberg spin chain, conformal invariance and the renormalization group, the approach of equilibrium, probability distributions, equilibrium and combinatorics

164p muasambanhan05 16-01-2024 3 0   Download

Lecture Physical science: Chapter 4 provide students with content about: classical physics; quanta of energy; bohr model of Hydrogen atom; particle-wave duality; heisenberg uncertainty principle; schrodinger equation;... Please refer to the detailed lecture content!

20p diepkhinhchau 18-09-2023 3 3   Download

We study the S=1 anisotropic antiferomagnetic Heisenberg model on a square lattice for all temperatures using the Popov-Fedotov representation of spin operators. In this representation the constraint of single particle site occupation is rigorously fulfilled by introducing an imaginary valued chemical potential.

11p vimoskva2711 02-01-2020 14 1   Download

We study magnetic properties of ordered phases in the Heisenberg model on a nonBravais lattice by means of a Popov - Fedotov trick, which takes into account a rigorous constraint of a single occupancy. We derive the magnetization and the free energy using sadle point approximation in the functional integral formalism. We illustrate the application of the Popov – Fedotov approach to the Heisenberg antiferromagnet on a honeycomb lattice.

10p viaphrodite2711 14-10-2019 7 0   Download

In this paper, we consider the mean-field Heisenberg model with deterministic external magnetic field. We prove a large deviation principle for Sn/n with respect to the associated Gibbs measure, where Sn/n is the scaled partial sum of spins. In particular, we obtain an explicit expression for the rate function.

9p vihermes2711 01-10-2019 13 0   Download

Having as a model the metric contact case of V. Brınzanescu; R. Slobodeanu, we study two similar subjects in the paracontact (metric) geometry: Distributions that are invariant with respect to the structure endomorphism φ, the class of vector fields of holomorphic type. As examples we consider both the 3-dimensional case and the general dimensional case through a Heisenberg-type structure inspired also by contact geometry.

10p danhdanh27 07-01-2019 22 1   Download

Based on an extended space-time symmetry a new attempt to search for links between general relativity and quantum mechanics is proposed. A simplified cylindrical model of gravitational geometrical dynamics leads to a microscopic geodesic description of strongly curved extradimensional space-time which implies a duality between an emission law of microscopic gravitational waves and the quantum mechanical equations of free elementary particles. Consequently, the Heisenberg indeterminism would originate from the time-space curvatures.

9p thuyliebe 09-10-2018 30 0   Download

We study the magnetic ordered phases of the spin-1/2 Heisenberg antiferromagnetic model with nearest J1 and next nearest neighbor J2 exchange interactions on the square lattice using fermionic representation of spin operators within Popov-Fedotov approach.The unphysical states are eliminated on each site by introducing an imaginary chemical potential. Working in local coordinate system for every site we investigate the different ordered phases in dependence on exchange parameters. At T = 0 we recover the conventional spin wave results.

8p thuyliebe 09-10-2018 28 0   Download