Synchronization boost with single-photon dissipation in the deep quantum regime

Abstract

Synchronization phenomena occur throughout nature. The van der Pol oscillator has been a paradigmatic model to investigate synchronization. Here we study the oscillator with additional single-photon dissipation in the deep quantum regime (defined to be γ 2 /γ 1 10), and we contrast it with the quantum regime at γ 2 /γ 1 ≈ 1. Our results show that in this regime: (i) the effect of squeezed driving effect on frequency entrainment is strongly suppressed, (ii) single-photon dissipation boosts synchronization, (iii) synchronization is bounded, and (iv) the limit-cycle is robust and insensitive to strong driving. We use these physical properties to define the crossover to the deep quantum regime. We also propose a synchronization measure based on directional statistics which is analytically calculated. These results reflect the intrinsic physical differences between synchronization in the quantum and deep quantum regimes.

Resonance interaction of two entangled atoms accelerating between two mirrors

“…We conclude by reemphasizing that it would be of further interest to see if resonance interaction of accelerating quantum emitters coupled to the electromagnetic vacuum could be controlled in real devices such as waveguides. It would be interesting to apply the present formalism [46,47] for radiative emission of atoms under various boundary conditions in realistic contexts of quantum transport [58,59].…”

Metastable quantum entrainment

“…boson number) in the family of QvdP systems [41,65], and hence the classical versus quantum system operation. In the limit γ 2 γ 1 ≫ 1 the QvdP oscillator is well approximated by a two-level system [40,53,65], while in the limit γ 2 γ 1 ≪ 1 the typical number of excitations becomes macroscopic. Indeed, in Ref.…”

“…As an alternative implementation strategy, a squeezed forcing has been reported to enhance entrainment in the quantum regime [60]. However, very deep into it, where the system behaves effectively as a few-level system, the enhancing effect of squeezing is limited [53].…”

Algebraic Theory of Quantum Synchronization and Limit Cycles under Dissipation

“…Intense work in the last decade has extended these non-linear results to the semi-classical domain of certain quantum systems with an infinite or very large local Hilbert space, e.g. quantum van der Pol oscillators, bosons, or large spin-S systems [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. These systems are usually understood successfully through mean-field methods or related procedures that neglect the full quantum correlations.…”