Multi-normal-mode splitting of a cavity in the presence of atoms: A step towards the superstrong-coupling regime

Abstract

Multi-normal-mode splitting peaks are experimentally observed in a system with Doppler-broadened twolevel atoms inside a relatively long optical cavity. In this system, the atoms-cavity interaction can reach the "superstrong coupling" condition with atoms-cavity coupling strength g √ N to be near or larger than the cavity free-spectral range ∆F SR. In such case, normal-mode splitting can occur in many cavity longitudinal modes to generate the multi-normal-mode splitting peaks, which can be well explained by the linear dispersion enhancement due to the largely increased atomic density in the cavity. Many new interesting phenomena might come out of this superstrong atoms-cavity coupling regime.

Controllable vacuum Rabi splitting and optical bistability of multi-wave-mixing signal inside a ring cavity

“…Recently, studies on atom-cavity interactions have been extended to a more composite system with an optical cavity and coherently prepared multilevel atoms [14], in which a narrow central peak was observed beside two broad sidebands (representing VRS) and can be well explained by the intracavity dispersion properties [15]. When the atom-cavity interaction reaches the "superstrong-coupling" condition with atom-cavity coupling strength G to be near or larger than the cavity free spectral range, multi-normal-mode splitting can be observed and well explained by the linear-dispersion enhancement due to the largely increased atomic density in the cavity [16,17].…”

Superstrong coupling of thin film magnetostatic waves with microwave cavity

“…However, in the thin film situation where multiple modes simultaneously couple with the cavity resonance, the mode splitting no longer directly reflects the coupling strength if the free spectral range (FSR) of the magnon modes is comparable with the coupling strength, which is known as the superstrong coupling regime. [31][32][33][34] Such a new coupling regime is very interesting in both fundamental study and practical applications. In a YIG thin film in free-space, different magnon modes are orthogonal with each other.…”

“…V C 2016 AIP Publishing LLC 119, 023905-1 regime: the superstrong coupling regime. [31][32][33][34] Within this regime, the eigenmodes of the thin film are significantly changed by the vacuum cavity field, giving rise to magnon hybridization. Using thin film geometry, a single sample can provide multiple modes which are individually addressable for signal processing, showing great potential for nonlinear magnon conversion and memory.…”

Comparison between optical bistabilities versus power and frequency in a composite cavity-atom system

“…In the meanwhile, the dynamical behaviors in a composite atom-cavity system with controllable linear and nonlinear optical properties are extensively studied. For example, the vacuum Rabi splitting (VRS) [14] characterized as a double-peaked transmission spectrum and associated with "bright polaritons" can be effectively modulated as two pairs of peak under the EIT regime due to the modified intracavity dispersion properties [15], which can make the atom-cavity interaction achieve the "superstrong-coupling" condition with the atom-cavity coupling strength manipulated to be close or larger than the cavity free spectral range [16,17].…”