Ergodicity from Nonergodicity in Quantum Correlations of Low-dimensional Spin Systems

TL;DR

This paper demonstrates that quantum correlations in low-dimensional spin systems can exhibit ergodic behavior independently of classical correlations, with implications for quantum computing decoherence.

Contribution

It reveals that quantum correlations can have ergodic properties distinct from classical correlations in specific quantum spin models.

Findings

Quantum correlations can be ergodic in certain spin systems.

Classical correlations and magnetizations do not necessarily exhibit ergodicity.

Results may impact understanding of decoherence in quantum computers.

Abstract

Correlations between the parts of a many-body system, and its time dynamics, lie at the heart of sciences, and they can be classical as well as quantum. Quantum correlations are traditionally viewed as constituted out of classical correlations and magnetizations. While that of course remains so, we show that quantum correlations can have statistical mechanical properties like ergodicity, which is not inherited from the corresponding classical correlations and magnetizations, for the transverse anisotropic quantum XY model in one-, two-, and quasi two-dimension, for suitably chosen transverse fields and temperatures. The results have the potential for applications in decoherence effects in realizable quantum computers.