Eur. Phys. J. Special Topics 227, 2013–2024 (2019)
https://doi.org/10.1140/epjst/e2018-800078-1

Regular Article

Classical spin simulations with a quantum two-spin correction

¹ Skolkovo Institute of Science and Technology, Skolkovo Innovation Centre, Nobel Street 3, Moscow 143026, Russia
² Department of Mathematics and Statistics, University of Saskatchewan, Saskatoon S7N 5E6, Canada
³ Lebedev Physical Institute of the Russian Academy of Sciences, Leninsky Prospect 53, Moscow 119991, Russia
⁴ Institute for Theoretical Physics, University of Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany

^a e-mail: p.navez@hzdr.de
^b e-mail: b.fine@skoltech.ru

Received: 28 April 2018
Received in final form: 13 August 2018
Published online: 24 January 2019

Abstract

Classical simulations of high-temperature nuclear spin dynamics in solids are known to accurately predict relaxation for spin 1/2 lattices with a large number of interacting neighbors. Once the number of interacting neighbors becomes four or smaller, classical simulations lead to noticeable discrepancies. Here we attempt to improve the performance of the classical simulations by adding a term representing two-spin quantum correlations. The method is tested for a spin-1/2 chain. It exhibits good performance at shorter times, but, at longer times, it is hampered by a singular behavior of the resulting equations of motion.