# Quantum Brownian motion for magnets

@article{Anders2022QuantumBM, title={Quantum Brownian motion for magnets}, author={Janet Anders and C R J Sait and Simon A. R. Horsley}, journal={New Journal of Physics}, year={2022}, volume={24} }

Spin precession in magnetic materials is commonly modelled with the classical phenomenological Landau–Lifshitz–Gilbert (LLG) equation. Based on a quantized three-dimensional spin + environment Hamiltonian, we here derive a spin operator equation of motion that describes precession and includes a general form of damping that consistently accounts for memory, coloured noise and quantum statistics. The LLG equation is recovered as its classical, Ohmic approximation. We further introduce resonant…

## 5 Citations

### Quantum Langevin Equation of a spin in a magnetic field : an analysis

- Physics
- 2022

We derive a quantum Langevin equation for a quantum spin in the presence of a magnetic ﬁeld and study its dynamics in the Markovian limit using the Ohmic bath model. We extend our analysis to the…

### Quantum-classical correspondence in spin-boson equilibrium states at arbitrary coupling

- Physics
- 2022

It is known that the equilibrium properties of nanoscale systems can deviate signiﬁcantly from standard thermodynamics due to their coupling to an environment. For the generalised θ -angled…

### Steady state in strong system-bath coupling regime: Reaction coordinate versus perturbative expansion.

- PhysicsPhysical review. E
- 2022

Motivated by the growing importance of strong system-bath coupling in several branches of quantum information and related technological applications, we analyze and compare two strategies currently…

### Magnetization switching in the inertial regime

- PhysicsPhysical Review B
- 2022

Kumar Neeraj, Matteo Pancaldi, ∗ Valentino Scalera, Salvatore Perna, Massimiliano d’Aquino, Claudio Serpico, and Stefano Bonetti 4, † Department of Physics, Stockholm University, 106 91 Stockholm,…

### Steady state in strong bath coupling: reaction coordinate versus perturbative expansion

- Physics
- 2021

Motivated by the growing importance of strong system-bath coupling in several branches of quantum information and related technological applications, we analyze and compare two strategies currently…

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