Article
Optics
Yoshihiro Iwata, Masabumi Miyabe, Katsuaki Akaoka, Ikuo Wakaida
Summary: Triple resonance excitation to the autoionizing Rydberg state of atomic strontium was studied for the isotope-selective photoionization of strontium-90 (90Sr). A new resonance ionization scheme, less affected by multiphoton ionization, showed potential for better isotopic selectivity with improved ionization efficiency.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Optics
Yoshihiro Iwata, Masabumi Miyabe, Shuichi Hasegawa
Summary: Measuring the DC Stark shifts of ten Rydberg levels of Sr-88, researchers found that the external electric field in the ionization region should be minimized to suppress its effect on observed spectra. The experimental data on the DC Stark shift and polarizability of Rydberg levels are valuable for future isotope-selective detection of Sr-90 using three-step resonance excitation.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Review
Chemistry, Analytical
Min Dang, Ruidong Liu, Fengshuo Dong, Bing Liu, Keyong Hou
Summary: On-line mass spectrometry (MS) techniques with high time resolution and elimination of potential artifacts are important for fast on-line analysis. Vacuum ultraviolet photoionization (VUV-PI) is a suitable ionization source for MS, offering advantages such as less fragments, high sensitivity, and short response time. This review discusses instrumental developments and characterization efforts on VUV-PI-MS, including modifications of the ionization source and sampling interfaces. Different ionization mechanisms and the influence of dopants are also explored, along with various applications.
TRAC-TRENDS IN ANALYTICAL CHEMISTRY
(2022)
Article
Instruments & Instrumentation
Jekabs Romans, Anjali Ajayakumar, Martial Authier, Frederic Boumard, Lucia Caceres, Jean-Francois Cam, Arno Claessens, Samuel Damoy, Pierre Delahaye, Philippe Desrues, Wenling Dong, Antoine Drouart, Patricia Duchesne, Rafael Ferrer, Xavier Flechard, Serge Franchoo, Patrice Gangnant, Sarina Geldhof, Ruben P. de Groote, Nathalie Lecesne, Renan Leroy, Julien Lory, Franck Lutton, Vladimir Manea, Yvan Merrer, Iain Moore, Alejandro Ortiz-Cortes, Benoit Osmond, Julien Piot, Olivier Pochon, Sebastian Raeder, Antoine de Roubin, Herve Savajols, Simon Sels, Dominik Studer, Emil Traykov, Juha Uusitalo, Christophe Vandamme, Marine Vandebrouck, Paul Van den Bergh, Piet Van Duppen, Klaus Wendt
Summary: In this paper, the first high-resolution laser spectroscopy results obtained at the GISELE laser laboratory of the GANIL-SPIRAL2 facility are presented for the first experiments with the S3-Low Energy Branch. Neutron-deficient radioactive isotopes of erbium and tin are studied, and the measured isotope-shift and hyperfine structure data for stable isotopes of these elements are presented. The laser setup is benchmarked using the atomic transitions of 4f126s2 3H6-* 4f12(3H)6s6p J = 5 (415 nm) for erbium isotopes and 5s25p2(3P0)-* 5s25p6s(3P1) (286.4 nm) for tin isotopes. Additionally, new isotope-shift data and corresponding field-shift F812 and mass-shift M812 factors are obtained for the 5s25p6s(3P1)-* 5s25p6p(3P2) (811.6 nm) atomic transition of tin isotopes.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
(2023)
Article
Optics
Sacha Schiffmann, Michel Godefroid
Summary: In this study, theoretical calculations of the electronic isotope shift factors for the 5d(7)6s(2) F-4(9/2) -> (odd, J = 9/2) line at 247.587 nm were presented to extract nuclear mean square radii and nuclear deformations of iridium isotopes. The atomic structure calculations were performed using the fully relativistic multiconfiguration Dirac-Hartree-Fock method and the relativistic configuration interaction method. Additional properties such as the sharing rule, Lande g factors, or phase tracking were employed to ensure an adequate description of the targeted odd level.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Chemistry, Analytical
J. Heide, S. Ehlert, T. Koziorowski, C. P. Ruger, A. Walte, R. Zimmermann
Summary: The development of orthogonal acceleration time-of-flight (oa-tof) technology has led to higher mass accuracy and resolving power compared to conventional linear/reflectron tof instruments. By spatially separating ion generation and orthogonal ion extraction, the oa-tof technology achieves a more accurate definition of starting energies and coordinates of ions. Continuous ion sources and high repetition rates are crucial for covering larger mass ranges without sacrificing temporal resolution. The combination of single-photon ionization (SPI) and resonance enhanced multi-photon ionization (REMPI) in the oa-tof system allows for comprehensive mass analysis and targeted monitoring.
Article
Nuclear Science & Technology
Shi-Wei Bai, Xiao-Fei Yang, Shu-Jing Wang, Yong-Chao Liu, Peng Zhang, Yin-Shen Liu, Han-Rui Hu, Yang-Fan Guo, Jin Wang, Ze-Yu Du, Zhou Yan, Yun-Kai Zhang, Yan-Lin Ye, Qi-Te Li, Yu-Cheng Ge, Chuang-Ye He
Summary: Collinear laser spectroscopy is a powerful tool for studying nuclear properties, and our developed apparatus successfully measured the optical spectra of Ca isotopes with excellent agreement compared to literature values. The system is now ready for use at radioactive ion beam facilities and paves the way for further development of higher-sensitivity collinear resonance ionization spectroscopy techniques.
NUCLEAR SCIENCE AND TECHNIQUES
(2022)
Article
Optics
Ye Liu, Da Chen, Fei Duan, Yonglin Yu
Summary: This paper proposes a high speed directly modulated and tunable distributed Bragg reflector laser based on an equivalent phase shift Bragg grating. By inserting a uniform waveguide in the grating section, the modulation bandwidth is extended and wavelength tuning is achieved by controlling the equivalent phase shift with an independent electrode.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Chemistry, Physical
Pravin P. Taware, Mukul G. Jain, Sreejith Raran-Kurussi, Vipin Agarwal, P. K. Madhu, Kaustubh R. Mote
Summary: Proteins rely on conformational changes to carry out function, and measuring these changes can provide insight into their function. In this study, the researchers combined different strategies to measure dipole-dipole couplings in nondeuterated systems at a high MAS frequency of 100 kHz. These strategies allow for the access of dipolar order parameters in a variety of systems at increasingly fast MAS frequencies.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Optics
A. C. Sahoo, P. K. Mandal, Jaya Mukherjee, Vas Dev, M. L. Shah
Summary: Resonance ionization spectroscopy of samarium was conducted in an atomic beam accompanied by a time-of-flight mass spectrometer. Isotope selective photoionization studies were performed on one of the even isotopes of samarium (Sm-152). High degree of isotopic selectivity (> 95%) for Sm-152 was achieved experimentally using multi-mode dye lasers. The isotope shifts for the first-and second-step transitions were determined through the use of isotope selective photoionization spectroscopy.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2022)
Article
Optics
S. T. Orson, C. D. McLaughlin, M. D. Lindsay, R. J. Knize
Summary: The study used a Rb cell and a wavemeter to measure the four hyperfine components of the 5S-6S transition near 993 nm, finding the absolute energies and isotope shift of the transitions. The researchers observed no AC Stark or light shift of the lines at 6 MHz spectral resolution under different Rb atom densities.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Optics
Liang-Cai Wen, Wen-Quan Jing, Chang-Ping Sun, Xuan-Hong Gao, Zhi-Hong Jiao, Guo-Li Wang, Jian-Hong Chen, Song-Feng Zhao
Summary: We numerically solve the three-dimensional time-dependent Schrodinger equation to comparatively study electron rotational asymmetries in photoionization of excited hydrogen atoms and photodetachment of fluorine anions. We find that single-photon ionization (or detachment) is more favorable when the electron initially corotates with the laser field. Interestingly, we observe that the electron rotational asymmetry in the excited hydrogen atom is completely opposite to that of the fluorine anion in the multiphoton ionization (or detachment) regime, which can be explained by the role of excited bound states analyzed through the total excitation probability in the excited hydrogen atom. Furthermore, we confirm the electron rotational asymmetry of 2p(+) 2p(-).
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2023)
Article
Chemistry, Physical
Kelly S. Meyer, John H. Westerfield, Sommer L. Johansen, Jasmine Keane, Anna C. Wannenmacher, Kyle N. Crabtree
Summary: This study investigates the three isomers of pyridyl using coupled cluster methods, providing spectroscopic parameters for simulating the rotational spectrum of each isomer and comparing with experimental data. The results guide new experimental investigations into the rotational spectra of these radicals.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Multidisciplinary Sciences
M. V. Suryanarayana
Summary: This study investigates a three-step resonant photoionization scheme for the enrichment of Nd-150 isotope, aiming for its application in neutrinoless double-beta decay detection. Optimum conditions have been derived for efficient enrichment, enabling the production of large quantities of highly enriched Nd-150 isotope in a short period of time.
SCIENTIFIC REPORTS
(2022)
Article
Spectroscopy
Min Zhou, Mei-Qi Guo, Jie Yu, Shuo Chai, Shu-Lin Cong
Summary: The study investigates the influence of molecular alignment and orientation on the photoelectron characteristics in the resonance-enhanced multiphoton ionization process, revealing that molecular pre-alignment and pre-orientation have different effects on photoionization.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Multidisciplinary
Daniel P. Zaleski, Raghu Sivaramakrishnan, Hailey R. Weller, Nathan A. Seifert, David H. Bross, Branko Ruscic, Kevin B. Moore, Sarah N. Elliott, Andreas Copan, Lawrence B. Harding, Stephen J. Klippenstein, Robert W. Field, Kirill Prozument
Summary: The study combines broadband rotational spectroscopy and detailed chemical modeling to observe products from the flash pyrolysis of acetone, revealing various minor products that are not adequately described by existing mechanisms. The inclusion of substitution reactions with rate constants and thermochemistry from automated ab initio kinetics predictions highlights the importance of such processes in product formation.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
Timothy J. Barnum, Gloria Clausen, Jun Jiang, Stephen L. Coy, Robert W. Field
Summary: This study investigates the vibrational autoionization dynamics of high-l Rydberg states using a long-range model for a simplified description. It explains the extensive angular momentum exchange between the ion-core and the Rydberg electron, as well as the dominant role of autoionization over predissociation in higher l states. The model also accurately predicts total decay rates and discusses potential applications in quantum state selection for molecular ion production.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Optics
M. I. Malicka, S. Ryzner, A. N. Heays, N. de Oliveira, R. W. Field, W. Ubachs, R. Hakalla
Summary: In this study, the rotational structure of the A(1)Pi(v = 2) level of (CO)-C-12-O-18 was re-examined using high-accuracy experimental data. Detailed spectroscopic information was obtained using complementary Fourier-transform techniques, leading to the determination of rotational constants and perturbation parameters through analysis of perturbations and interactions.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Multidisciplinary Sciences
Jasmin Borsovszky, Klaas Nauta, Jun Jiang, Christopher S. Hansen, Laura K. McKemmish, Robert W. Field, John F. Stanton, Scott H. Kable, Timothy W. Schmidt
Summary: The dicarbon molecule C-2 is responsible for the green color in comets and is observed to require absorbing two photons and undergo two forbidden transitions for photodissociation, with a bond dissociation energy determined to be 602.804(29) kJ.mol(-1).
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Yaqing Zhang, Jiaojian Shi, Xian Li, Stephen L. Coy, Robert W. Field, Keith A. Nelson
Summary: Water molecules have been extensively studied through rotational spectroscopy due to their significance in chemistry and biology. Recently developed 2D terahertz rotational spectroscopy has enabled the observation of high-order rotational coherences and correlations between previously unobservable rotational transitions. The results reveal the presence of previously unseen metastable water complexes with multiple preferred bimolecular geometries, showcasing the sensitivity of rotational correlations to molecular interactions in the gas phase.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Chemistry, Physical
Jun Jiang, Hong-Zhou Ye, Klaas Nauta, Troy Van Voorhis, Timothy W. Schmidt, Robert W. Field
Summary: Despite the long history of spectroscopic studies of the C-2 molecule, fundamental questions about its chemical bonding are still being debated. This study proposes a global multi-state diabatic model to understand the complex electronic structure and bonding of C-2.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Physics, Atomic, Molecular & Chemical
Piyush Mishra, Alexander W. Hull, Timothy J. Barnum, Brett A. McGuire, Robert W. Field
Summary: This study reports on the chirped-pulse Fourier-transform rotational spectroscopy of furan, which reveals its vibrationally excited state modes. It is found that the inertial defect is a useful quantity for extracting structural information of vibrational modes of planar asymmetric tops. These findings are of great importance for astronomical searches of furan and its vibrational states.
JOURNAL OF MOLECULAR SPECTROSCOPY
(2022)
Article
Spectroscopy
Stanislaw Ryzner, Marzena I. Malicka, Alan N. Heays, Robert W. Field, Nelson de Oliveira, Wojciech Szajna, Wim Ubachs, Rafal Hakalla
Summary: This study provides an improved description of the A1P(v = 1) energy region in the 13C18O isotopologue, using modern experimental methods and deperturbation analysis.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2022)
Article
Physics, Atomic, Molecular & Chemical
Wojciech Szajna, Ryszard Kepa, Andrzej Para, Izabela Piotrowska, Stanislaw Ryzner, Robert W. Field, Alan N. Heays, Rafal Hakalla
Summary: An extensive high-resolution visible wavelength emission spectrum of AlH, covering eight bands of the A(1) Pi - X-1 Sigma(+) system, was observed for the first time using a Fourier-transform spectrometer. The strongest 0 - 0 band had a signal-to-noise ratio of 9000:1. Molecular constants and rotational term values were derived for different energy levels of AlH, and Dunham parameters for the A(1) Pi state were determined for the first time. Small shifts in energy levels were observed and attributed to possible interactions between different states.
JOURNAL OF MOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Piyush Mishra, Alexander W. Hull, Stephen L. Coy, Robert W. Field
Summary: We used rotationally resolved Chirped-Pulse Fourier Transform millimeter-wave spectroscopy to investigate the photodissociation dynamics of 1,3,5-Triazine, which forms 3 HCN molecules. The state-specific vibrational population distribution (VPD) of the photofragments provides mechanistic details of the reaction. The results suggest a sequential dissociation mechanism of symmetric-Triazine initiated by 266 nm radiation, with an asymmetric partitioning of vibrational energy among the HCN photofragments.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Applied
Weikun Tian, Wen Jun Wee, An Qu, Billy Jun Ming Lim, Prithvi Raj Datla, Vanessa Pei Wen Koh, Huanqian Loh
Summary: We demonstrate a parallel rearrangement algorithm that uses multiple mobile tweezers to independently sort and compress atom arrays in a way that naturally avoids atom collisions. Our algorithm offers a reduced move complexity compared to both single-tweezer algorithms and existing multitweezer algorithms, with a high degree of parallelism.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Ruizhe Shen, Tianqi Chen, Mohammad Mujahid Aliyu, Fang Qin, Yin Zhong, Huanqian Loh, Ching Hua Lee
Summary: This study provides a method for physically probing nonunitary phase transitions in nonequilibrium settings by detecting kinked dynamical magnetization responses, which enables the observation of Yang-Lee edge singularities (YLES). Scaling analyses based on nonunitary time evolution circuit accurately recover the exponents uniquely associated with the corresponding nonunitary conformal field theory (CFT). An explicit proposal for observing YLES criticality in Floquet quenched Rydberg atomic arrays with laser-induced loss is provided, paving the way towards a universal platform for simulating non-Hermitian many-body dynamical phenomena.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Piyush Mishra, Alexander W. Hull, Stephen L. Coy, Robert W. Field
Summary: We used Chirped-Pulse Fourier Transform millimeter-wave spectroscopy to study the photodissociation dynamics of 1,3,5-Triazine to produce 3 HCN molecules. The state-specific vibrational population distribution of the photofragments provides details of the reaction mechanism. This photodissociation was performed using 266 nm radiation transverse to a supersonic jet. The observed vibrational excitation suggests an asymmetric partitioning of vibrational energy among the HCN photofragments, indicating a sequential dissociation mechanism.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Physics, Multidisciplinary
Mohammad Mujahid Aliyu, Luheng Zhao, Xiu Quan Quek, Krishna Chaitanya Yellapragada, Huanqian Loh
Summary: This study demonstrates a significant increase in scalability of Na-23 atom arrays using D-1 magic wavelength tweezers, confirming a predicted magic wavelength at 615.87 nm and achieving high loading efficiency for single traps and one-dimensional arrays of atoms. These methods are applicable to alkali atoms and have potential applications in dipolar molecule assembly, Rydberg dressing, and fermionic systems.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Ilia Tutunnikov, Long Xu, Robert W. Field, Keith A. Nelson, Yehiam Prior, Ilya Sh Averbukh
Summary: Chirality and chiral molecules play a key role in modern chemical and biochemical industries. Research has shown that interaction between cross-polarized THz pulses and chiral molecules can induce an enantioselective orientation in the molecules, which may have significant implications for separation techniques in the future.
PHYSICAL REVIEW RESEARCH
(2021)
