Mechanisms of decoherence in weakly anisotropic molecular magnets

TL;DR

This paper investigates decoherence in weakly anisotropic magnetic molecules like V15, identifying thermal dipolar fluctuations as a key factor, and suggests these molecules could serve as prototypes for quantum computing studies.

Contribution

It introduces a model for decoherence due to thermal dipolar fluctuations and demonstrates that quantum coherence can be maintained at around 0.5 K in V15 molecules.

Findings

Thermal dipolar fluctuations significantly contribute to decoherence.

Quantum coherence persists at approximately 0.5 K in V15 molecules.

V15 molecules are promising for quantum computer research.

Abstract

Decoherence mechanisms in crystals of weakly anisotropic magnetic molecules, such as V15, are studied. We show that an important decohering factor is the rapid thermal fluctuation of dipolar interactions between magnetic molecules. A model is proposed to describe the influence of this source of decoherence. Based on the exact solution of this model, we show that at relatively high temperatures, about 0.5 K, the quantum coherence in a V15 molecule is not suppressed, and, in principle, can be detected experimentally. Therefore, these molecules may be suitable prototype systems for study of physical processes taking place in quantum computers.