Details

Autor(en) / Beteiligte

• Begg, S E
• Green, A G
• Bhaseen, M J

Titel

Fluctuations and non-Hermiticity in the stochastic approach to quantum spins

Ist Teil von

• Journal of physics. A, Mathematical and theoretical, 2020-11, Vol.53 (50), p.50

Ort / Verlag

IOP Publishing

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We investigate the non-equilibrium dynamics of isolated quantum spin systems via an exact mapping to classical stochastic differential equations. We show that one can address significantly larger system sizes than recently obtained, including two-dimensional systems with up to 49 spins. We demonstrate that the results for physical observables are in excellent agreement with exact results and alternative numerical techniques where available. We further develop a hybrid stochastic approach involving matrix product states. In the presence of finite numerical sampling, we show that the non-Hermitian character of the stochastic representation leads to the growth of the norm of the time-evolving quantum state and to departures for physical observables at late times. We demonstrate approaches that correct for this and discuss the prospects for further development.