Quantum synchronization as a local signature of super- and subradiance

Abstract

We study the relationship between the collective phenomena of super-and subradiance and spontaneous synchronization of quantum systems. To this aim we revisit the case of two detuned qubits interacting through a pure dissipative bosonic environment, which contains the minimal ingredients for our analysis. By using the Liouville formalism, we are able to find analytically the ultimate connection between these phenomena. We find that dynamical synchronization is due to the presence of longstanding coherence between the ground state of the system and the subradiant state. We finally show that, under pure dissipation, the emergence of spontaneous synchronization and of subradiant emission occur on the same time scale. This reciprocity is broken in the presence of dephasing noise.

Synchronizing quantum harmonic oscillators through two-level systems

“…A few uncoupled spins interacting with a common environment [17] as well as ensembles of dipoles [18] have been considered. More recently, collective behavior of many spins has been studied in order to establish a connection between synchronization processes and superradiance or subradiance [19]. A further extension present in the literature is the dynamical alignment of optomechanical systems [20][21][22].…”

Machine Learning Applied to Quantum Synchronization‐Assisted Probing

“…The emergence of quantum synchronization has been recently reported in several systems and, in particular, in spin systems . This phenomenon can emerge not only in the well‐known case of systems exhibiting self‐sustained oscillations, but also during transient dynamics . Furthermore, the role played by dissipation and decoherence in synchronization has been explored not only in transient regimes but also in decoherence free subspaces and in the presence of self‐sustained oscillations (in opto‐mechanichal systems).…”

Observing quantum synchronization blockade in circuit quantum electrodynamics

“…when the limit cycle steady states of the oscillators are quantum states with no classical analog. Previous work on quantum synchronization has focused mainly on theoretically identifying and characterizing differences between classical and quantum synchronization [7][8][9][10][11][12][13][14][15][16][17][18] and on potential applications of the latter [19][20][21]. Experimental observation of quantum synchronization phenomena is hindered by the stringent requirements of high quantum coherence and strong nonlinearities, both of which are also key requirements for quantum computation.…”