Giant enhancement of quantum decoherence by frustrated environments
S. Yuan, M. I. Katsnelson+, H. De Raedt
Department of Applied Physics, Materials Science Center, University of Groningen, NL-9747 AG Groningen, The Netherlands
+Institute of Molecules and Materials, Radboud University of Nijmegen, NL-6525 ED Nijmegen, The Netherlands
PACS: 03.65.Yz, 75.10.Nr
Abstract
This Letter studies the decoherence in a system of two
antiferromagnetically coupled spins that interact with a spin bath
environment. Systems are considered that range from the rotationally
invariant to highly anisotropic spin models, have different topologies and
values of parameters that are fixed or are allowed to fluctuate randomly. We
explore the conditions under which the two-spin system clearly shows an
evolution from the initial spin-up - spin-down state towards the maximally
entangled singlet state. We demonstrate that frustration and, especially,
glassiness of the spin environment strongly enhances the decoherence of the
two-spin system.