Decoherence and pointer states in small antiferromagnets: A benchmark test

Abstract

We study the decoherence process of a four spin-1/2 antiferromagnet that is coupled to an environment of spin-1/2 particles. The preferred basis of the antiferromagnet is discussed in two limiting cases and we identify two $exact$ pointer states. Decoherence near the two limits is examined whereby entropy is used to quantify the $robustness$ of states against environmental coupling. We find that close to the quantum measurement limit, the self-Hamiltonian of the system of interest can become dynamically relevant on macroscopic timescales. We illustrate this point by explicitly constructing a state that is more robust than (generic) states diagonal in the system-environment interaction Hamiltonian.

21 pages

References in corpus (8)

• Quantum Computing
• Spin decoherence of magnetic atoms on surfaces
• Uncovering many-body correlations in nanoscale nuclear spin baths by central spin decoherence
• On the relation between decoherence and spontaneous symmetry breaking
• Decoherence by a spin thermal bath: Role of the spin-spin interactions and initial state of the bath
• Entanglement-induced Decoherence and Energy Eigenstates
• Evolution of a quantum spin system to its ground state: Role of entanglement and interaction symmetry
• Quantum Decoherence Scaling with Bath Size: Importance of Dynamics, Connectivity, and Randomness

Cited by in corpus (2)

• Relaxation, thermalization and Markovian dynamics of two spins coupled to a spin bath
• Decoherence of a singlet-triplet superposition state under dipolar interactions of an uncorrelated environment