Critical quantum fluctuations and photon antibunching in optomechanical systems with large single-photon cooperativity

Abstract

A pertinent question in cavity optomechanics is whether reaching the regime of large single-photon cooperativity, where the single-photon coupling rate exceeds the geometric mean of the cavity and mechanical decay rates, can enable any new phenomena. We show that in some multimode optomechanical systems, the single-photon cooperativity can indeed be a figure of merit. We first study a system with one cavity mode and two mechanical oscillators, which combines the concepts of levitated optomechanics and coherent scattering with standard dispersive optomechanics. Later, we study a more complicated setup involving three cavity modes which does not rely on levitated optomechanics and only features dispersive optomechanical interactions with direct cavity driving. These systems can effectively realize the degenerate or the nondegenerate parametric oscillator models known from quantum optics, but in the unusual finite-size regime for the fundamental mode(s) when the single-photon cooperativity is large. We show that the response of these systems to a coherent optical probe can be highly nonlinear in probe power even for average photon occupation numbers below unity. The nonlinear optomechanical interaction has the peculiar consequence that the probe drive will effectively amplitude-squeeze itself. For large single-photon cooperativity, this occurs for small occupation numbers, which enables observation of nonclassical antibunching of the transmitted probe photons due to a destructive interference effect. Finally, we show that as the probe power is increased even further, the system enters a critical regime characterized by intrinsically nonlinear dynamics and non-Gaussian states.

Cavity Optomechanics with Photonic Bound States in the Continuum

“…These estimated values place our system in the non-resolved sideband regime and firmly in the ultrastrong single-photon coupling regime with g 0 /Ω m ∼ 2.3, complementing previous works [21,64]. Further, assuming a realistically achievable mechanical Q-factor of Q m ∼ 10 8 [34, 65] yields a single-photon cooperativity [1,66] of C = 4g 2 0 Q m /(κΩ m ) ∼ 2.2 × 10 6 , which is similar to Ref. [64] and three orders of magnitude larger than in Refs.…”

Normal Mode Splitting in a Cavity Optomechanical System with a Cubic Anharmonic Oscillator

“…Thus the optomechanical system with a cubic anharmonic oscillator gives an alternative approach to produce stronger optomechanical coupling. Future research might explore these studies in the strong coupling regime at the single photon level [50].…”

Simultaneously enhanced photon blockades in two microwave cavities via driving a giant atom

“…In recent years, single photon sources are extensively applied in the fields of quantum optics and quantum information technologies [1][2][3]. To generate the single photon source, many schemes based on photon blockade (PB) effect have been proposed by using different physical systems, including cavity quantum electrodynamics (QED) system [4][5][6][7][8], superconducting circuit system [9], optomechanical system [10][11][12][13][14][15], and so on. The PB, also known as the conventional PB (CPB), results from the anharmonicity of energy level in the system [16][17][18], where photons in the nonlinear cavity will block the transmission of subsequent photons.…”