Article
Physics, Multidisciplinary
Hai Yi, Hongjun Zhang, Hui Sun
Summary: We study the electromagnetic properties of a dense atomic gas medium with Doppler effect on four energy levels. The results show that due to the electromagnetically induced transparency, the relative permittivity and permeability of the medium can be simultaneously negative with low absorption in the same detuning interval. Moreover, by adjusting the temperature, control field intensity, and atomic density, the nonreciprocal negative refraction resulting from the Doppler effect can be achieved, and the nonreciprocity frequency band can be regulated.
Article
Optics
Shih-Si Hsiao, Wei-Kai Huang, Yi-Min Lin, Jia-Mou Chen, Chia-Yu Hsu, Ite A. Yu
Summary: In this study, the temporal profile of biphotons generated from a hot atomic vapor via four-wave mixing was systematically studied. An analytical expression of the biphoton's spectral profile in the Doppler-broadened medium was derived. The study found that the spectral profile is mainly determined by the effect of electromagnetically induced transparency (EIT) and the biphoton's temporal profile influenced by the Doppler broadening is an exponential-decay function.
Article
Quantum Science & Technology
Hansol Jeong, Heewoo Kim, Han Seb Moon
Summary: A high-performance telecom-wavelength biphoton source from a hot 87Rb atomic vapor cell is reported, achieving a maximum biphoton cross-correlation of 44 under high optical depth and a spectral width of approximately 300 MHz, with an estimated coincidence count rate of 38,000 cps mW-1.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Optics
Chia-Yu Hsu, Yu-Sheng Wang, Jia-Mou Chen, Fu-Chen Huang, Yi-Ting Ke, Emily Kay Huang, Weilun Hung, Kai-Lin Chao, Shih-Si Hsiao, Yi-Hsin Chen, Chih-Sung Chuu, Ying-Cheng Chen, Yong-Fan Chen, Ite A. Yu
Summary: Utilizing the all-copropagating scheme in a hot atomic vapor, researchers have achieved high brightness biphotons with tunable linewidth and competitive generation rates. The generated biphotons exhibit high purity and surpass previous works in terms of linewidth and spectral brightness, offering potential applications in quantum information processing.
Review
Immunology
Xudong Zhao, Qiang Shan, Hai-Hui Xue
Summary: TCF1 plays essential roles in early T cell development and exhibits versatile, context-dependent functions in mature T cells. It is required for the self-renewal of stem-like CD8(+) T cells and regulates T cell responses effectively.
NATURE REVIEWS IMMUNOLOGY
(2022)
Article
Physics, Multidisciplinary
Nguyen Van Ai, Nguyen Huy Bang, Le Van Doai
Summary: We have achieved a negative refractive index with reduced absorption in a three-level Λ-type atomic gas medium under Doppler broadening. The conditions for obtaining negative refractive index under Doppler broadening are different from those without Doppler broadening, with a higher coupling laser intensity required. The frequency band of negative refractive index is significantly expanded with Doppler broadening, but the amplitude decreases with increasing temperature or Doppler width.
Article
Materials Science, Multidisciplinary
Kangkang Li, Yuan Zhao, Yishan Qin, Zhili Chen, Yin Cai, Yanpeng Zhang
Summary: Biphoton states play a crucial role in quantum technologies, especially in quantum information processing. This experimental study focuses on shaping the temporal correlation of biphotons in a hot Rb atomic ensemble through four-wave mixing, showing potential for enriching biphoton features with additional dressing fields.
ADVANCED PHOTONICS RESEARCH
(2021)
Article
Thermodynamics
Michael John Evans, Alfonso Chinnici
Summary: The study shows that water vapor in hot flames plays a significant role in reducing soot and affecting temperature fields.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Article
Chemistry, Analytical
Daisuke Kozaki, Masanobu Mori, Shinichi Hamasaki, Tomotaka Doi, Souma Tanihata, Atushi Yamamoto, Takeshi Takahashi, Koutarou Sakamoto, Shigeto Funado
Summary: A simple method using enclosed quartz cell and cold vapour-atomic absorption spectrometry is proposed for determining total inorganic mercury in solution, achieving similar precision to conventional methods while reducing sample volume, reductant, and cost.
ANALYTICAL METHODS
(2021)
Article
Physics, Multidisciplinary
Di Feng-Qing, Jia Ning, Qian Jing
Summary: Based on a four-level inverted-Y atomic system, this study demonstrates the limitation of linewidth-narrowing in the electromagnetic induced absorption platform. By using an auxiliary control field, the linewidth limitation is constrained by a coherence decay rate between two hyperfine ground states, resulting in a significantly narrower absorption linewidth compared to previous schemes. Numerical simulations confirm the theoretical predictions and show a longer response time and reduced Doppler effect on linewidth-narrowing.
ACTA PHYSICA SINICA
(2022)
Article
Optics
Mahdi Yousefi, Peter F. Bernath, Mike Dulick, Manfred Birk, Georg Wagner
Summary: The study investigated the spectral characteristics of methane molecules by measuring the spectra under different hydrogen pressures and temperatures, and studying the changes in parameters such as line width and frequency shift. Experimental data showed that the line width and frequency shift parameters exhibit different patterns with variations in temperature and pressure, influenced by the rotational quantum number. These research findings provide a theoretical basis for further understanding the spectral behavior of methane molecules.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Optics
Wenjie Yue, Tao Chen, Wei Kong, Zhongpeng Ji, Lu Yin, Genghua Huang, Zhiping He, Rong Shu
Summary: The study demonstrated a YDFL based on a multifunctional AOTF, allowing for flexible wavelength generation through changing the drive signal, with a wide wavelength tuning range and high resolution.
Article
Chemistry, Analytical
Lulu Zhang, Yongbiao Yang, Ni Zhao, Jun He, Junmin Wang
Summary: This paper presents a free-induction-decay type optically-pumped rubidium atomic magnetometer driven by a radio-frequency magnetic field. The influences of different parameters on the FID signal amplitude and FWHM have been investigated. The sensitivities of the magnetometer for single-pass and triple-pass probe beam cases have been compared, showing that the triple-pass probe beam significantly enhances the FID signal amplitude and sensitivity.
Article
Physics, Multidisciplinary
D. Pizzey, J. D. Briscoe, F. D. Logue, F. S. Ponciano-Ojeda, S. A. Wrathmall, I. G. Hughes
Summary: This tutorial reviews the theory and experimental techniques of spectroscopy of hot atomic vapours. Aimed at novice scientists, it provides an introduction to the field while highlighting the work of expert practitioners and the importance of relevant software packages.
NEW JOURNAL OF PHYSICS
(2022)
Article
Astronomy & Astrophysics
D. Cont, F. Yan, A. Reiners, L. Nortmann, K. Molaverdikhani, E. Palle, Th Henning, I Ribas, A. Quirrenbach, J. A. Caballero, P. J. Amado, S. Czesla, F. Lesjak, M. Lopez-Puertas, P. Molliere, D. Montes, G. Morello, E. Nagel, S. Pedraz, A. Sanchez-Lopez
Summary: We studied the atmosphere of the ultra-hot Jupiter WASP-33b using emission spectroscopy. By analyzing high-resolution spectra from multiple observation nights, we detected the spectral signatures of several elements for the first time and confirmed the presence of other previously studied elements. We also found evidence of an inverted temperature profile and a higher metallicity compared to the Sun.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Physics, Applied
Xichang Zhang, Shenchao Jin, Weizhi Qu, Yanhong Xiao
Summary: The study investigates NMOR magnetometers and finds that the best sensitivity is achieved in the low power regime with no light squeezing. Insights on parameter optimization and choice of detection observables are provided, emphasizing the delicate trade-off between atomic responses and various noise sources. The results could have practical significance in optical atomic magnetometry.
APPLIED PHYSICS LETTERS
(2021)
Article
Physics, Multidisciplinary
Xingda Lu, Wanxia Cao, Wei Yi, Heng Shen, Yanhong Xiao
Summary: The study demonstrates nonreciprocal light transport in a quantum system of hot atoms by engineering the dissipative atomic reservoir. By tuning the phase of collective atomic excitations through external driving fields, interchannel quantum correlations originating from interactions with the engineered reservoir are observed. This nonreciprocal transport in a quantum optical atomic system opens up new opportunities for atom-based nonreciprocal optics and quantum simulations with coupled optical channels.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Shenchao Jin, Han Bao, Junlei Duan, Xingda Lu, Mingfeng Wang, Kai-Feng Zhao, Heng Shen, Yanhong Xiao
Summary: The spin-squeezed state is a multi-body entangled state of great interest for precision measurements. The adiabatic pulse control of the pump field in state preparation is essential for noise suppression, which is necessary for achieving spin squeezing and has significance for quantum metrology applications.
PHOTONICS RESEARCH
(2021)
Article
Instruments & Instrumentation
Ziting Chen, Bojeong Seo, Mingchen Huang, Mithilesh K. Parit, Peng Chen, Gyu-Boong Jo
Summary: The method utilizes the characteristic response of a narrow laser-line filter to achieve high spectral purity and low-intensity noise of the diode laser through active feedback to the injected laser. This approach is cost-effective and eliminates the need for bulky devices like Fabry-Perot interferometers or wavemeters, simplifying potential applications of injection locking of diode lasers in optical systems.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Physics, Multidisciplinary
Xi-Wang Luo, Chuanwei Zhang, Shengwang Du
Summary: This research establishes a quantum pseudo-anti-PT (pseudo-APT) symmetry which, when spontaneously broken, leads to the generation of an exceptional point that can be utilized for ultraprecision quantum sensing applications.
PHYSICAL REVIEW LETTERS
(2022)
Article
Optics
Xin Meng, Zhiwei Hu, Xingda Lu, Wanxia Cao, Xichang Zhang, Haowei Li, Ying Hu, Wei Yi, Yanhong Xiao
Summary: In this experiment, tunable non-Hermitian coupling is demonstrated in an atomic-vapor cell, where atomic coherences in different optical channels are dissipatively coupled through atomic motion. By introducing a far-detuned light wall in the reservoir between the optical channels, the inter-channel coupling term can be switched from dissipative to coherent. The tunable non-Hermiticity is confirmed through measurements of the inter-channel light transport, and the setup can serve as a building block for the experimental study of exotic non-Hermitian criticality.
PHOTONICS RESEARCH
(2022)
Article
Engineering, Multidisciplinary
Ka Hung Chan, Shengwang Du, Xian Chen
Summary: This study presents a theoretical exploration of surface step characterization using reflected incoherent-light differential interference microscopy, with consideration of the optical diffraction effect. By integrating localization analysis, a quantitative differential interference optical system is developed, which demonstrates high axial resolution in measuring surface height variation. The experiment successfully characterizes nanometer-size steps with subnanometer accuracy, indicating the potential of optical differential interference microscopy for real-time surface structure characterization in micro/nano-electromechanical systems.
MEASUREMENT SCIENCE AND TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
Dongdong Hao, Lin Wang, Xingda Lu, Xuzhen Cao, Suotang Jia, Ying Hu, Yanhong Xiao
Summary: Recent experimental advances in creating dissipative couplings provide a new route for engineering exotic lattice systems and exploring topological dissipation. Using a spatial lattice of atomic spin waves, we experimentally realize a dissipative version of the Su-Schrieffer-Heeger (SSH) model. The dissipative spectrum of the topological lattices shows edge modes within a dissipative gap. This work opens up the possibility of realizing non-Hermitian topological quantum optics through dissipative couplings.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Rong Chen, Xiao Tang, Yuxuan Zhao, Zeyu Shen, Meng Zhang, Yusheng Shen, Tiantian Li, Casper Ho Yin Chung, Lijuan Zhang, Ji Wang, Binbin Cui, Peng Fei, Yusong Guo, Shengwang Du, Shuhuai Yao
Summary: A deep-learning-based single-frame super-resolution microscopy method is proposed, which allows for high spatiotemporal resolution imaging of cellular dynamics. It overcomes the limitations of multi-frame super-resolution microscopy in terms of long acquisition times and phototoxicity.
NATURE COMMUNICATIONS
(2023)
Article
Biology
Zeyu Shen, Bowen Jia, Yang Xu, Jonas Wessen, Tanmoy Pal, Hue Sun Chan, Shengwang Du, Mingjie Zhang, Rohit Pappu
Summary: Formation of membraneless organelles or biological condensates via phase separation expands the cellular organelle repertoire. In this study, an adaptive single-molecule imaging method was developed to track individual molecules in various biological condensates. The method enables measurements of concentrations, motion behavior, and molecular exchanges between condensed and dilute phases. The findings offer insights into the molecular mechanisms underlying the assembly and dynamics of biological condensates.
Article
Quantum Science & Technology
Eun Oh, Xuanying Lai, Jianming Wen, Shengwang Du
Summary: The promise of universal quantum computing requires scalable control interactions between single or multiple qubits. Current leading candidate platforms for quantum computing, superconducting circuits, trapped ions, and neutral atom arrays, suffer from strong interaction with environmental and control noises resulting in qubit decoherence. Photons, on the other hand, have advantages of being well decoupled from the environment and having high speed and timing capabilities. This article proposes a universal distributed quantum computing scheme based on photons and atomic-ensemble-based quantum memories, showcasing the potential of a photon-atom network hybrid approach.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Optics
Yue Jiang, Yefeng Mei, Shengwang Du
Summary: We propose a macroscopic phenomenological formula for quantum Langevin equations describing two coupled phase-conjugated electromagnetic fields with linear loss (gain) and complex nonlinear coupling coefficient. This formula, obtained from the coupling matrix, preserves the field commutation relations and correlations without requiring knowledge of microscopic light-matter interaction and atomic structures. We validate the formula by numerically confirming its consistency with the microscopic Heisenberg-Langevin theory in the context of spontaneous four-wave mixing in a double-four-level atomic system. We also find that a complex-valued nonlinear coupling coefficient can induce noise even in the absence of linear gain or loss. Finally, we apply the quantum Langevin equations to study the effects of linear gain and loss, complex phase mismatching, and complex nonlinear coupling coefficient on entangled photon pair generation, particularly their temporal quantum correlations.
Article
Optics
Xi-Wang Luo, Chuanwei Zhang, Irina Novikova, Chen Qian, Shengwang Du
Summary: This study proposes a wavelength conversion device for single-photon polarization qubits using continuous-variable quantum teleportation. It efficiently converts qubits between near-infrared and telecom wavelength, potentially paving the way for long-distance quantum networks.
Article
Optics
Ying Zuo, Chenfeng Cao, Ningping Cao, Xuanying Lai, Bei Zeng, Shengwang Du
Summary: Quantum state tomography (QST) is crucial for experimental quantum information processing, and optical neural networks (ONN) show promising potential in photonic polarization qubit QST.
ADVANCED PHOTONICS
(2022)
Article
Quantum Science & Technology
Zeyang Li, Boris Braverman, Simone Colombo, Chi Shu, Akio Kawasaki, Albert F. Adiyatullin, Edwin Pedrozo-Penafiel, Enrique Mendez, Vladan Vuletic
Summary: In a high-finesse optical cavity, the interaction between an atomic ensemble and a light mode easily reaches the strong-coupling regime, where quantum effects dominate. This interaction can generate both atom-light and atom-atom entanglement, and conditions are determined to maximize the entanglement-induced gain in quantum sensors and atomic clocks.
