Thermal Fluctuations Enhance Order-from-Disorder of Quantum Correlations in Quenched Disordered Spin Models

TL;DR

This paper demonstrates that thermal fluctuations can enhance quantum correlations in quenched disordered spin models, revealing an order-from-disorder phenomenon that is influenced by temperature and system parameters.

Contribution

It shows that quenched averaged quantum correlations can exhibit order-from-disorder effects in disordered spin models, with temperature tuning amplifying these effects.

Findings

Quantum correlations show order-from-disorder in disordered spin models.

Temperature tuning can enhance quantum correlations.

Quenched averages relate to quantum critical points.

Abstract

We consider paradigmatic quenched disordered quantum spin models, viz., the XY spin glass and random-field XY models, and show that quenched averaged quantum correlations can exhibit the order-from-disorder phenomenon for finite-size systems as well as in the thermodynamic limit. Moreover, we find that the order-from-disorder can get more pronounced in the presence of temperature by suitable tuning of the system parameters. The effects are found for entanglement measures as well as for information-theoretic quantum correlation ones, although the former show them more prominently. We also observe that the equivalence between the quenched averages and their self-averaged cousins -- for classical and quantum correlations -- is related to the quantum critical point in the corresponding ordered system.