Article
Optics
Dmitry Obydennov, Konstantin B. Yushkov, Vladimir Ya. Molchanov
Summary: We developed a tunable system for shaping the spectral and spatial frequency of ultrashort laser pulses using acousto-optic filters. This system allows for the creation of arbitrary axially symmetric multi-wavelength field configurations and enables high-speed control. Experimental results demonstrate the independent generation of different colored intensity distributions from a single laser beam using this system.
Article
Multidisciplinary Sciences
Ilya Kuprov, David Wilkowski, Nikolay Zheludev
Summary: It is commonly believed that electromagnetic spectra of atoms and molecules can be fully described by interactions involving electric and magnetic multipoles. However, recent studies have shown that interactions between light and matter also involve toroidal multipoles. This study explores the feasibility of a previously unexplored type of spectroscopy involving toroidal dipolar interactions, which have been largely neglected. The results show that considering the spin-dependent term in relativistic quantum mechanics allows for the distinction of toroidal dipole transitions from electric multipole and magnetic dipole transitions.
Article
Optics
A. Golovizin, D. Tregubov, D. Mishin, D. Provorchenko, N. Kolachevsky
Summary: This article introduces a compact vacuum system for laser cooling and spectroscopy of neutral thulium atoms, achieving compactness through adjustments in configuration. The system demonstrates potential for use in optical atomic clocks.
Article
Optics
Hiromitsu Sawaoka, Alexander Frenett, Abdullah Nasir, Tasuku Ono, Benjamin L. Augenbraun, Timothy C. Steimle, John M. Doyle
Summary: We demonstrate and characterize Zeeman-Sisyphus (ZS) deceleration of a beam of ytterbium monohydroxide. Our method uses a combination of large magnetic fields (-2.5 T) and optical spin-flip transitions to decelerate molecules while scattering only -10 photons per molecule. We study the challenges associated with the presence of internal molecular perturbations among the excited electronic states and discuss the methods used to overcome these challenges, including a modified ZS decelerator using microwave and optical transitions.
Article
Physics, Multidisciplinary
Miao Wang, Zheng Chen, Yao Huang, Hua Guan, Ke-Lin Gao
Summary: Micromotion induced by the radio-frequency field plays a significant role in the systematic frequency shifts of optical frequency standards. Optically trapping ions in a dipole trap composed of a high-power laser field has the potential to eliminate micromotion effectively, as demonstrated in the setup using a 532 nm laser at 10 W power aiming to trap a single Ca-40(+) ion. The dipole laser's beam waist of several microns provides a strong dipole potential for the optical trapping of a single Ca-40(+) ion.
Article
Optics
Wenliang Liu, Ningxuan Zheng, Xiaofeng Wang, Jing Xu, Yuqing Li, Vladimir B. Sovkov, Peng Li, Yongming Fu, Jizhou Wu, Jie Ma, Liantuan Xiao, Suotang Jia
Summary: The experiment presents a method for quickly producing Bose-Einstein condensates (BECs) of Na-23 atoms, creating a pure F = 1 BEC of approximately 1.1 x 10^5 sodium atoms with a fast forced evaporation process. The system reliably generates the condensate at a rate exceeding 10^5 atoms every approximately 8 seconds. Additionally, the lifetimes of the mixed F = 1 condensate and the spin components (m ( F ) = 0, m ( F ) = +1) were compared.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Optics
Junyi Duan, Xiaochi Liu, Yadong Zhou, Xin-Biao Xu, Liang Chen, Chang-Ling Zou, Zhendong Zhu, Zhilong Yu, Ning Ru, Jifeng Qu
Summary: Magneto-optical traps based on grating chips simplify cold atom physical package architectures significantly. A high-diffraction-efficiency grating magneto-optical trap (GMOT) design and fabrication are reported. The fabricated grating chip achieved a diffraction efficiency of up to 40% and successfully trapped a large number of atoms. The proposed atom chip can be used for compact cold atom clocks and other cold atom-based quantum sensors.
OPTICS COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Jongmin Lee, Grant Biedermann, John Mudrick, Erica A. Douglas, Yuan-Yu Jau
Summary: This study demonstrates the generation of a cold-atom ensemble in a sub-millimeter diameter hole in a transparent membrane, achieving temperatures as low as 10 μK through sub-Doppler cooling. The membrane MOT device allows for efficient loading of cold atoms into an optical trap for strong atom-light interaction, representing a key step towards the development of a photonic atom trap integrated platform (ATIP).
SCIENTIFIC REPORTS
(2021)
Article
Optics
Jun Li, Tian Ma
Summary: This article introduces a novel optical metamaterial that can achieve sharp Fano-type resonances by tuning the asymmetry. The proposed metamaterial exhibits a strong magnetic toroidal dipole (MTD) resonance and has a narrow linewidth, making it suitable for optical sensing applications to monitor the refractive index of the surrounding medium.
OPTICS COMMUNICATIONS
(2022)
Article
Optics
Hyeonwoo Lee, Mingyu Lee, Hyeung Joo Lee, Juwon Yoon, Kishan Dholakia, Kyunghwan Oh
Summary: In this study, a novel all-fiber Bessel-like beam generator (BBG) was proposed and experimentally demonstrated to transport a dielectric particle over a distance exceeding 2mm. This was achieved by optimizing the multimode interference (MMI) in the BBG structure to create a Bessel-like beam with a propagation invariant length (PIL) and selecting an appropriate laser wavelength to suppress thermal effects. The impact of varying the diameter of the MMI region on the PIL and the transverse intensity profile of the Bessel-like beam was analyzed. This research paves the way for fiber optic applications such as novel beam shaping, optical transport, and optical imaging.
OPTICS AND LASERS IN ENGINEERING
(2023)
Article
Optics
Yaxun Zhang, Yu Zhou, Xiaoyun Tang, Zhen Wang, Yu Zhang, Zhihai Liu, JianZhong Zhang, Jun Yang, Libo Yuan
Summary: This study presents an optical trap based on a single-mode fiber that can trap two particles simultaneously, which could facilitate advancements in the fields of biology, biophysics, and soft matter.
Article
Physics, Multidisciplinary
Yash Lokare
Summary: This paper discusses the quantitative description of the second law of thermodynamics in small-scale systems over short time scales through fluctuation theorems. The transient fluctuation theorem has been demonstrated to be applicable to small-scale systems perturbed from initial equilibrium steady-state distribution, both theoretically and experimentally. Additionally, experimental results show that the transient fluctuation theorem applies not only to equilibrium steady-state distributions, but also to nonequilibrium steady-state distributions of an ideal colloidal system in an accelerated frame of reference in the long-time limit.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Optics
Qin Tang, Dandan Zhang, Tingting Liu, Wenxing Liu, Qinghua Liao, Jizhou He, Shuyuan Xiao, Tianbao Yu
Summary: In this Letter, an all-dielectric metasurface composed of perforated magneto-optical thin films is proposed to enhance the magneto-optical effects. The numerical results show significantly increased Faraday and Kerr rotations near the toroidal dipole resonance. Furthermore, an environment refractive index sensor with high sensitivities and figures of merit is designed based on the resonantly enhanced effects.
Article
Chemistry, Multidisciplinary
Mingke Jin, Xu Zhang, Xuan Liu, Changwen Liang, Jixun Liu, Zixian Hu, Kingfai Li, Guochao Wang, Jun Yang, Lingxiao Zhu, Guixin Li
Summary: The use of diffractive optical elements in single-beam magneto-optical traps (MOTs) provides a new approach for compact cold atom sources. However, previous single-beam MOT systems have low and unbalanced optical efficiency, which affects the quality of trapped atoms. To address this problem, we developed a centimeter-scale dielectric metasurface optical chip with dynamic phase distributions that splits a single incident laser beam into five separate beams with well-defined polarization states and uniform energy distributions. The measured diffraction efficiency of the metasurface is up to 47%. A single-beam MOT integrated with the metasurface optical chip was used to trap 87Rb atoms with a population of approximately 1.4 x 108 and temperatures around 7.0 μK. This concept provides a promising solution for the development of ultracompact cold atom sources.
Article
Multidisciplinary Sciences
Anita Devi, Sumit Yadav, Arijit K. K. De
Summary: By combining wide-field and point detection modalities, this study explores the dynamics of optical trapping under femtosecond pulsed excitation. The radial trajectories of trapped particles are mapped from backscatter fluctuations, while the temporal evolution of two-photon fluorescence marks the onset of trapping involving multiple particles. The simultaneous confocal detection of backscatter and two-photon fluorescence estimates axial trap stiffness, revealing short-time trapping dynamics and inter-particle interactions within the trap. These findings are crucial for achieving controlled manipulation using optical nonlinearity under femtosecond pulsed excitation.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Multidisciplinary
M. Mousley, G. Thirunavukkarasu, M. Babiker, J. Yuan
NEW JOURNAL OF PHYSICS
(2017)
Article
Physics, Multidisciplinary
S. M. Lloyd, M. Babiker, G. Thirunavukkarasu, J. Yuan
REVIEWS OF MODERN PHYSICS
(2017)
Review
Optics
Mohamed Babiker, David L. Andrews, Vassilis E. Lembessis
Article
Optics
K. Koksal, Vasileios E. Lembessis, J. Yuan, M. Babiker
Article
Optics
K. Koksal, V. E. Lembessis, J. Yuan, M. Babiker
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2020)
Article
Optics
K. Koksal, M. Babiker, V. E. Lembessis, J. Yuan
Summary: The study examines the chirality and helicity of linearly polarised Laguerre-Gaussian (LG) beams, showing that under specific conditions, these beams exhibit significant chirality and helicity density distributions. Different winding numbers result in distinct chirality and helicity distributions, with the convergence phase of the beam contributing differently to changes in these distributions at different planes along the beam propagation.
OPTICS COMMUNICATIONS
(2021)
Article
Optics
K. Koksal, M. Babiker, V. E. Lembessis, J. Yuan
Summary: This paper systematically derives the general form of the optical helicity density for elliptically polarized waves, taking into account the contributions of the axial electric and magnetic fields. It confirms that the space integral of the term related to l in the density vanishes completely.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2022)
Article
Physics, Multidisciplinary
Stephen M. Barnett, Fiona C. Speirits, Mohamed Babiker
Summary: In summary, this paradox questions how a Gaussian beam, which has zero orbital angular momentum, can drive a quadrupole transition that requires the transfer of angular momentum to an absorbing atom.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Optics
M. Babiker, J. Yuan, V. E. Lembessis, K. Koksal
Summary: We demonstrate that uniformly linearly-polarised paraxial vortex modes carrying orbital angular momentum have zero spin angular momentum density, but exhibit non-zero helicity density distributions. This confirmed that the mode possesses chirality and can engage with chiral matter. Furthermore, it was found that the space integral of helicity and chirality densities vanish identically for all optical vortex modes carrying orbital angular momentum.
OPTICS COMMUNICATIONS
(2022)
Article
Optics
K. Koksal, M. Babiker, V. E. Lembessis
Summary: Recent studies have shown that radially-polarised optical modes with helical wave fronts can be generated in the laboratory. These modes carry only axial optical angular momentum (AM) and have zero spin angular momentum (SAM), indicating the presence of only orbital angular momentum (OAM) and no SAM. The helicity of these modes is proportional to the winding number (l) and displays chirality. When applied to Laguerre-Gaussian (LG) modes, the total helicity is determined by the action constant (Q) multiplied by the sign of (l/|l|), and this result holds for LG modes of any magnitude of the winding number (l). The magnitude of the action constant and hence the helicity decrease for LG modes with large beam waist (w0).
Article
Optics
K. Koksal, M. Babiker, V. E. Lembessis, J. Yuan
Summary: An orthonormal set of optical vortex modes, named the polarized truncated optical Bessel (TOB) set, is proposed and identified. This set of modes possesses both orbital and spin angular momentum and can be realized by placing a circular aperture in the path of an optical Bessel beam.
Article
Optics
V. E. Lembessis, K. Koksal, J. Yuan, M. Babiker
Summary: In this study, the optical dipole potential energy of a two-level atom interacting with a circularly polarized Laguerre-Gaussian laser beam of small waist is examined. The presence of a longitudinal electric field component in the beam leads to the appearance of a chiral term in the optical dipole potential energy. A bi-chromatic vortex interaction scheme is proposed to achieve a fully chiral optical dipole potential.
Article
Optics
Smail Bougouffa, Mohamed Babiker
Article
Optics
Smail Bougouffa, Mohamed Babiker
Article
Optics
G. Thirunavukkarasu, M. Mousley, M. Babiker, J. Yuan
