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Physics

Spectroscopy

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Displaying 26 - 50 of 948

Chirped magneto-optical trap of molybdenum

December 12, 2025
Author(s)
Sai Naga Manoj Paladugu, Nickolas Pilgram, Stephen Eckel, Eric Norrgard
We have directly loaded a cryogenic beam of molybdenum atoms into a magneto-optical trap. By chirping the detuning of the trapping lasers, we were able to enhance the number of atoms loaded into the trap by more than a factor of 2. We optimize the trapped

UV-enabled Defect Engineering in Multilayer GaSe and InSe and UV Writing of the Grating Pattern

November 25, 2025
Author(s)
Bhojraj Bhandari, Sinto Varghese, Amar Ghimire, Bimal Neupane, Sicheng Wang, Yan Jiang, Roberto Rodrigues, Sergiy Krylyuk, Albert Davydov, Yuanxi Wang, Hao Yan, Jingbiao Cui, Yuankun Lin
III−VI post-transition-metal chalcogenides are layered semiconductor materials that exhibit direct band gaps in multilayers. Defect engineering is essential in 2D layered semiconductors for functional devices. Here, we report defect engineering in

Population-resolved measurement of an avoided crossing of light-dressed states

November 17, 2025
Author(s)
Noah Schlossberger, Nikunjkumar Prajapati, Eric Norrgard, Stephen Eckel, Christopher Holloway
A two-level system coupled by a coherent field is a ubiquitous model in atomic and molecular physics. While the resulting avoided crossing of light-dressed states has been extensively probed spectroscopically, such measurements typically reveal only the

A formal Fe(III)/(V) redox couple in an intercalation electrode

October 15, 2025
Author(s)
Hari Ramachandran, Edward Mu, Eder Lomeli, Augustin Braun, Masato Goto, Kuan Hsu, Jue Liu, Zhelong Jiang, Kipil Lim, Grace Busse, Brian Moritz, Joshua Kas, John Vinson, John Rehr, Jungjin Park, Iwnetim Abate, Yuichi Shimakawa, Edward Solomon, Wanli Yang, William Gent, Thomas Devereaux, William Chueh
Iron redox cycling between low-valent oxidation states of FeII and FeIII drives crucial processes in nature. The FeII/III redox couple charge compensates the cycling of lithium iron phosphate, a positive electrode (cathode) for lithium-ion batteries. High

Speciation of cesium in a radiocesium-bearing microparticle emitted from Unit 1 during the Fukushima nuclear accident by XANES spectroscopy using transition edge sensor

September 5, 2025
Author(s)
Yoshio Takahashi, Shinya Yamada, Hikaru Miura, Yuichi Kurihara, Oki Sekizawa, Kiyofumi Nitta, Tadashi Hashimoto, Masato Tanaka, Minako Kurisu, Shinji Okada, Takaaki Itai, Hiroki Suga, Teruhiko Kashiwabara, Kohei Sakata, Hideyuki Tatsuno, Ryota Hayakawa, Hirotaka Suda, Takaya Ohashi, Yoshitaka Ishisaki, Takuma Okumura, Yuto Ichinohe, Tasuku Hayashi, Yuki Imai, Hirofumi Noda, Toru Tamagawa, Tadaaki Isobe, Toshiyuki Azuma, William Doriese, Joel Ullom, Daniel Swetz, Malcolm Durkin, Galen O'Neil, Satoshi Kohjiro, Shogo Higaki, Daisuke Tsumune, Masayoshi Yamamoto, Tomoya Uruga
The chemical state of radiocesium (RCs) was determined using X-ray absorption near-edge structure (XANES) in fluorescence mode and microbeam X-ray fluorescence (μ-XRF) mapping for the cesium (Cs) incorporated in a radiocesium-bearing silica microparticle

Quantitative Analysis of the Crystallinity of CoFeB Layers in Magnetic Random-Access Memory (MRAM) Stacks Using Extended X-ray Absorption Fine Structure Spectroscopy

September 3, 2025
Author(s)
Bruce Ravel, Matthias Gottwald, Christian Lavoie, Jean Jordan-Sweet, Steve Brown, Guohan Hu
Using Extended X-ray Absorption Fine Structure spectroscopy (EXAFS), we demonstrate a quantitative method to evaluate the degree of crystallization of thin CoFeB-based structures used in Spin Transfer Torque Magnetic Random-Access Memory (STT-MRAM). This

Collision Induced Absorption in HITRAN2024: Enhanced and Improved Data for Atmospheric and Planetary Studies

August 8, 2025
Author(s)
J. Terragni, I.E. Gordon, Erin Adkins, C. Boulet, A. Campargue, D. Chistikov, A. Finenko, H. Finkenzeller, H. Fleurbaey, R. J. Hargreaves, R.K. Hanson, J.-M. Hartmann, A. Klingberg, E. Kohler, A. O. Koroleva, D. Mondelain, G. Piccioni, S. Stefani, C. L. Strand, H. Tran, M. Turbet, A. Vigasin, F. Vitali, R. Volkamer, C. Wei
Collision-Induced Absorption (CIA) phenomena play a key role in the atmospheric energy balance, making their accurate parametrization a decisive factor in modeling planetary atmospheres. This is the primary reason why the HITRAN spectroscopic database

Survey of the updated O2 line list in the HITRAN 2024 spectroscopic database

August 8, 2025
Author(s)
Erin Adkins, Joseph Hodges
Light-matter interactions involving molecular oxygen (O2) span numerous decades in the frequency of electromagnetic radiation and are important tomany thermophysical and thermochemical mechanisms, ranging from atmospheric remote sensing of greenhouse gases

High-Stability Single-Ion Clock with 5.5 x 10^-19 Systematic Uncertainty

July 14, 2025
Author(s)
Mason Marshall, Daniel Rodriguez Castillo, Willa Dworschack, Alexander Aeppli, Kyungtae Kim, Dahyeon Lee, William Warfield, Nicholas Nardelli, Tara Fortier, Jun Ye, David Ray Leibrandt, David Hume
We report a single-ion optical atomic clock with fractional frequency uncertainty of 5.5 x 10^-19 and frequency stability of 3.5 x 10^-16/sqrttau/s}, based on quantum logic spectroscopy of a single 27Al+ ion. A co-trapped 25Mg+ ion provides sympathetic

Non-resonant Two-photon X-ray Absorption in Cu

July 10, 2025
Author(s)
Joshua Kas, John Rehr, Joachim Stohr, John Vinson
We present a real-space Green's function theory and calculations of two-photon x-ray absorption (TPA). Our focus is on nonresonant K-shell TPA in metallic Cu, which has been observed experimentally at intense x-ray free electron laser (XFEL) sources. The

Solvent Exclusion Effect on Infrared Absorption Spectroscopy

July 9, 2025
Author(s)
Young Lee, Charles Camp, Bonghwan Chon, Seong-Min Kim, Sang Hak Lee
Absorption spectroscopy of a solution containing an analyte solute typically uses the transmission through a solvent as a reference based on the assumption that the solvent does not absorb light. However, when a solvent absorbs light, the resulting

Multi-laboratory measurements of 12CH4 2n3 band line parameters. Part I: Line intensities with relative combined standard uncertainties at the permille level

July 5, 2025
Author(s)
Zachary Reed, Manfred Birk, Yan Tan, Christina Cecelski, Georg Wagner, Shui-Ming Hu, David Long, Rui-Heng Yin, Joseph Hodges
We present accurate transition intensities for the R0 to R10 manifolds of 12CH4 in the 2ν3 tetradecad region determined independently by two separate laboratories through cavity ring-down spectroscopy and Fourier Transform spectroscopy measurements. Each

Impact of Ni-like metastable states and hyperfine quenching on charge state distribution in an EBIT

June 30, 2025
Author(s)
Chowdhury Abrar Faiyaz, Endre Takacs, Timothy Burke, FNU Dipti, Galen O'Neil, Adam Hosier, Hunter Staiger, Joseph Tan, Yuri Ralchenko
We show the effects of ladder ionization and hyperfine quenching on charge state distributions and spectral features of ions in electron beam ion trap (EBIT) devices. Ladder ionization with intermediate excitation of metastable states proceeds at lower

The Role of Cu+3 in Oxygen Evolution Activity of Copper-Oxides

May 1, 2025
Author(s)
Pooja Basera, Yang Zhao, Angel Garcia-Esparza, Finn Babbe, Neha Bothra, John Vinson, Dimosthenis Sokaras, Junko Yano, Shannon Boettcher, Michal Bajdich
Cu-based oxides and hydroxides represent an important class of materials from a catalytic and corrosion perspective. In this study, we investigate the formation of bulk and surface Cu+3 species stable under water oxidation catalysis in alkaline media. So

Compact Blackbody Radiation Atomic Sensor: Measuring Temperature using Optically Excited Atoms in Vapor Cells

April 17, 2025
Author(s)
David La Mantia, Mingxin Lei, Nikunjkumar Prajapati, Noah Schlossberger, Matthew Simons, Christopher Holloway, Julia Scherschligt, Stephen Eckel, Eric Norrgard
We demonstrate a blackbody radiation thermometer based on optically excited rubidium atoms in a vapor cell. Operating as a calibrated contact thermometer from 308K to 343 K, we realize temperature uncertainty as low as 0.04 %, and statistical temperature

Contributions of argon, nitrogen, and oxygen to air broadening in the oxygen A-band

April 16, 2025
Author(s)
Leah Stevenson, Mitchio Okumura, Joseph Hodges, Erin Adkins
The oxygen (O2) A-band is used to determine the air mass in ground- and space-based remote sensing measurements because the O2 mixing ratio in Earth's atmosphere is constant. Because errors in the retrieved air mass propagate to measurements of target gas

Efficient Energy Transfer and Photoluminescence Enhancement in 2D MoS2/bulk InSe van der Waals Heterostructures

April 13, 2025
Author(s)
Michael Altvater, Christopher Stevens, Nicholas Pike, Joshua Hendrickson, Rahul Rao, Sergiy Krylyuk, Albert Davydov, Deep Jariwala, Ruth Patcher, Michael Snure, Nicholas Glavin
Heterostructures between 2D and 3D electron systems remain critically important in developing novel and efficient optoelectronic and electronic devices. In this study, a vertical heterojunction between monolayer MoS2 and bulk InSe was developed. This

New beyond-Voigt line-shape pro le recommended for the HITRAN database

March 27, 2025
Author(s)
Piotr Wcislo, N. Stolarczyk, M. Slowinski, H. Jozwiak, Daniel Lisak, R. Ciurylo, A. Cygan, F. Schreier, C.D. Boone, A. Castrillo, L. Gianfrani, Y. Tan, S-M. Hu, Erin Adkins, Joseph Hodges, H. Tran, H.N. Ngo, J.M- Hartmann, A. Campargue, S. Beguier, R.J. Hargreaves, L.S. Rothman, I.E. Gordon
Parameters associated with the collisional perturbation of spectral lines are essential for modeling the absorption of electromagnetic radiation in planetary atmospheres. The HITRAN molecular spectroscopic database provides these parameters, although

A low-cost ultrasonic absorption spectrometer mainly using off-the-shelf parts

March 11, 2025
Author(s)
Michelle Crouse, Malgorzata Musial, Jason Widegren, Jacob Pawlik, Bryan Bosworth, Nathan Orloff, Aaron Hagerstrom, Angela Stelson, Robert Lirette
Ultrasonic absorption spectroscopy can probe intermolecular interactions that inform research into chemical engineering and pharmaceutical manufacturing processes. The only commercial ultrasonic spectrometer costs over one hundred thousand dollars, putting
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