Speaker
Description
Continuously driven non-linear systems show interesting behaviour such as bistability and self-oscillations, and have recently come into the focus of theoretical and experimental research again. The system’s nonlinearity fundamentally changes the response to constant driving such that it can even facilitate time-periodic, self-oscillating states. An interesting question regards the interplay of many self-oscillating entities with coupled dynamics due to an interaction between the individual oscillators. A collective response of the ensemble has been observed for certain coupling regimes and is known as synchronisation. This transition towards a synchronised state has been used to describe the rhythmic flashing of fireflies and the chirp pattern of snowy tree crickets. Even the applause of an audience can transition from random clapping to a collective rhythmic pattern, which can be explained within the framework of synchronisation.
To experimentally study the synchronisation transition for many oscillators one needs a coupling between a large number of constituents while also maintaining tunability of the system parameters. So far, these demands on the system have proven challenging to meet experimentally. Recently, we have observed the emergence of synchronisation in a driven-dissipative hot Rydberg vapour [1]. Synchronisation occurs in a strongly-driven three-level ladder scheme in Rb where we couple the intermediate $^5$P$_{3/2}$ state to a Rydberg state. The synchronised state manifests as oscillations of the transmission of the probe beam through the atomic vapour. Wide tunability of the system parameters as well as fast oscillation frequencies on the order of 10 kHz allow for an exploration of the synchonisation transition over a large parameter space and with many constituent coupled oscillators.
[1] K. Wadenpfuhl and C. S. Adams, Emergence of Synchronization in a Driven-Dissipative Hot Rydberg Vapor, PRL 131, 143002 (2023)
