Transient synchronisation and quantum coherence in a bio-inspired vibronic dimer

Synchronisation is a collective phenomenon widely investigated in classical oscillators and, more recently, in quantum systems. However it remains unclear what features distinguish synchronous behaviour in these two scenarios. Recent works have shown that investigating synchronisation dynamics in open quantum systems can give insight into this issue. Here we study transient synchronisation in a bio-inspired vibronic dimer, where electronic excitation dynamics is mediated by coherent interactions with intramolecular vibrational modes. We show that the synchronisation dynamics of local mode displacements exhibit a rich behaviour which arises directly from the distinct time-evolutions of different vibronic quantum coherences. Furthermore, our study shows that coherent energy transport in this bio-inspired system is concomitant with the emergence of positive synchronisation between mode displacements. Our work provides further understanding of the relations between quantum coherence and synchronisation in open quantum systems and suggests an interesting role for coherence in biomolecules, that of promoting synchronisation of vibrational motions driven out of thermal equilibrium

Synchronization phase as an indicator of persistent quantum correlations between subsystems

Spontaneous synchronization is a collective phenomenon that can occur in both dynamical classical and quantum systems. Here, we analyze the spontaneous synchronization dynamics of vibrations assisting energy transfer in a bio-inspired system. We find the emergence of a constant nonzero “synchronization phase” between synchronized vibrational displacements as the natural frequencies of the oscillators are detuned. This phase difference arises from the asymmetric participation of local modes in the long-lived synchronized state. Furthermore, we investigate the relationships between the synchronization phase, detuning and the degree of quantum correlations between the synchronizing subsystems and find that the synchronization phase captures how quantum correlations persistently exceed classical correlations during the dynamics. We show that our analysis applies to a variety of spontaneously synchronizing open quantum systems. Our work therefore opens up a promising avenue to investigate nontrivial quantum phenomena in complex biomolecular and nanoscale chemical systems