Dressed Gain from the Parametrically Amplified Four-Wave Mixing Process in an Atomic Vapor.

Zhaoyang Zhang,Junling Che,Dan Zhang,Yanpeng Zhang,Feng Wen,Min Xiao,Changbiao Li

doi:10.1038/srep15058

Zhaoyang Zhang, Junling Che + Show 5 more

Open Access

https://doi.org/10.1038/srep15058

Copy DOI

Journal: Scientific Reports	Publication Date: Oct 14, 2015
Citations: 33	License type: CC BY 4.0

Affiliation: Xi'an Jiaotong University, Nanjing University

Abstract

With a forward cone emitting from the strong pump laser in a thermal rubidium atomic vapor, we investigate the non-degenerate parametrically amplified four-wave mixing (PA-FWM) process with dressing effects in a three-level “double-Λ” configuration both theoretically and experimentally. By seeding a weak probe field into the Stokes or anti-Stokes channel of the FWM, the gain processes are generated in the bright twin beams which are called conjugate and probe beams, respectively. However, the strong dressing effect of the pump beam will dramatically affect the gain factors both in the probe and conjugate channels, and can inevitably impose an influence on the quantum effects such as entangled degree and the quantum noise reduction between the two channels. We systematically investigate the intensity evolution of the dressed gain processes by manipulating the atomic density, the Rabi frequency and the frequency detuning. Such dressing effects are also visually evidenced by the observation of Autler-Townes splitting of the gain peaks. The investigation can contribute to the development of quantum information processing and quantum communications.

Highlights

Induce the generation of a pair of strongly correlated Stokes and anti-Stokes fields[28] with high efficiency, which can produce squeezed states with narrow bandwidth and low frequency[20,29]
We demonstrate the parametrically amplified FWM (PA-FWM) process with dressing effects in an off-resonant “double-Λ ” arrangement by establishing a forward cone[30] in a thermal rubidium atomic vapor both theoretically and experimentally
With the weak probe beam seeded into the Stokes or anti-Stokes channel in the FWM process generated from the strong pump beam, the gain processes can be obtained in both the conjugate and probe channels

Summary

Introduction

Induce the generation of a pair of strongly correlated Stokes and anti-Stokes fields[28] with high efficiency, which can produce squeezed states with narrow bandwidth and low frequency[20,29]. The EIA effect can interact and compete with the gain process in the probe field, which can inevitably render the change of squeezing state as well as the amplification factor. Such interaction and competition are investigated by the signal intensity evolution dependences of the dressed gain on the atomic density, the Rabi frequency and the frequency detuning of the pump laser. The fundamental study on the dressed gain of the bright twin beams can be effectively conducive to the development of quantum information processing such as entangled images and the generation of correlated photons source as well as squeezing states

Methods

Results

Conclusion