Optical quantum states based on hot atomic ensembles and their applications

Abstract

.The four-wave mixing process in atomic ensembles has many important applications in quantum information. We review recent progress on the generation of optical quantum states from the four-wave mixing process in hot atomic ensembles, including the production of two-beam, multi-beam, and multiplexed quantum correlated or entangled states. We also review the applications of these optical quantum states in implementing quantum information protocols, constructing SU(1,1) quantum interferometers, and realizing quantum plasmonic sensing. These applications indicate that the four-wave mixing process in hot atomic ensembles is a promising platform for quantum information processing, especially for implementing all-optical quantum information protocols, constructing SU(1,1) interferometers, and realizing quantum sensing.

Spectral non-hermitian quantization line shape controlled by phonon dressing in various phases of Eu3+:BiPO4

“…Fig. 3(a) shows the evolution of a broad peak obtained from a (0.5 : 1) sample of Eu 3+ :BiPO 4 with varying the time gate from t 1 (0.1 ms) to t 5 (1.5 ms) at 300 K. According to eqn (1)-( 3), the second-order fluorescence (FL) and the third-order Stokes (ES/ AS) for the Eu 3+ :BiPO 4 samples can be represented as r (2) FL and r (3) S/AS , respectively. The variation in the time gate influences the natural lifetime (eqn ( 6)), which brings a conversion in the energy levels ( 5 D 0 to 7 F 1 , MJ=0,AE1 ) as shown in Fig.…”

“…Rare-earth ion-doped crystals are not only ideal candidates for luminescent and photonic applications, but they also hold great potential for solid-state devices, such as quantum information storage and signal processing, in contrast with atomic vapors. [1][2][3][4] These properties make them ideal contenders for luminescent and photonic applications. 5,6 Rare-earth-doped crystals are also interesting candidates for quantum memory applications in terms of their decay rate and line shape.…”

Remote multicolour excitation laser-induced fluorescence imaging studies

“…The application of this technique has been demonstrated under controlled laboratory conditions and at construction site sites, revealing the adaptability of the system [6]. Notably, work carried out in City A during brick samples and stadium events highlighted the system's ability to recognise subtle differences in material properties using composite spectra synthesised from multiple excitation wavelengths.…”

Controllable transitions among phase-matching conditions in a single nonlinear crystal

“…Quantum light sources, including single-photon sources and entangled photon sources, are fundamental resources for the study of quantum information processing [1,2] . One of the most widely used methods for preparing quantum light sources is spontaneous parametric downconversion (SPDC) in a nonlinear optical crystal [3,4] .…”