Persistent dynamic entanglement from classical motion: How bio-molecular machines can generate non-trivial quantum states

TL;DR

This paper explores how classical motion in biological molecules can generate and sustain quantum entanglement under various noise conditions, expanding previous models to include different decoherence scenarios and conformational changes.

Contribution

It demonstrates that persistent dynamic entanglement can occur beyond simple models, including in non-Markovian environments and through conformational changes in molecular machines.

Findings

Entanglement persists in non-bosonic and non-Markovian models.

Conformational changes can induce entanglement in unfavorable conditions.

Mechanisms may be exploited by biological molecular machines.

Abstract

Very recently [Phys. Rev. E 82, 021921 (2010)] a simple mechanism was presented by which a molecule subjected to forced oscillations, out of thermal equilibrium, can maintain quantum entanglement between two of its quantum degrees of freedom. Crucially, entanglement can be maintained even in the presence of very intense noise, so intense that no entanglement is possible when the forced oscillations cease. This mechanism may allow for the presence of non-trivial quantum entanglement in biological systems. Here we significantly enlarge the study of this model. In particular, we show that the persistent generation of dynamic entanglement is not restricted to the bosonic heat bath model, but it can also be observed in other decoherence models, e.g. the spin gas model, and in non-Markovian scenarios. We also show how conformational changes can be used by an elementary machine to generate entanglement even in unfavorable conditions. In biological systems, similar mechanisms could be exploited by more complex molecular machines or motors.