Article
Physics, Multidisciplinary
Yuechun Jiao, Jingxu Bai, Rong Song, Shanxia Bao, Jianming Zhao, Suotang Jia
Summary: In this study, we demonstrated a tuned dipole interaction between Rydberg atoms by employing a controllable electric field in a cold cesium ensemble. By precisely tuning the electric field, Forster resonant interaction and adiabatic resonance energy transfer between the nP and nS Rydberg states were achieved. The results showed that the dipole interaction-induced blockade effect is stronger than the van der Waals interaction-induced blockade effect.
FRONTIERS IN PHYSICS
(2022)
Article
Multidisciplinary Sciences
Nicolas Zuber, Viraatt S. V. Anasuri, Moritz Berngruber, Yi-Quan Zou, Florian Meinert, Robert Loew, Tilman Pfau
Summary: Researchers have discovered a new type of molecular ion based on the interaction between the ionic charge and a flipping-induced dipole of a highly excited electron, called Rydberg atom. This molecular ion has a bond length of several micrometres. Using a high-resolution ion microscope, they have measured the vibrational spectrum and spatially resolved the bond length and angular alignment of the molecule. Due to the large bond length, the molecular dynamics are extremely slow.
Article
Physics, Multidisciplinary
J. Andrijauskas, J. Vogel, A. Mokhberi, F. Schmidt-Kaler
Summary: In this study, Rydberg series spectroscopy was performed on a single trapped Ca-40(+) ion to determine the ionization energy and quantum defect values, confirming their scaling properties for Rydberg ions. The precise spectroscopic data obtained can be used for unambiguous addressing of Rydberg levels of Ca+ ions, further facilitating quantum information processing.
PHYSICAL REVIEW LETTERS
(2021)
Article
Optics
Evan C. Jones, Zachery P. Andreula, Barry C. Walker
Summary: We studied the polarization and Stark-shifted binding energy for ultraintense lasers interacting with highly charged ions from beryllium to uranium at intensities up to 1022 W cm-2. The induced dipole and Stark shifts for the bound states can reach up to 0.1ea0 and 50Eh. Calculations of tunneling showed significant impacts of polarization and Stark shifts on the ionization rate, but they counteract each other. This work resolves the long-standing question of the quantitative success of field-free derivations of tunneling response for highly charged ions in relativistic, ultrahigh-intensity experiments. Using a scaling relationship, the results can be generalized to give the induced electric dipole for any species across an intensity range from 1015 to 1022 W cm-2.
Article
Optics
Attila Toth, Sandor Borbely, Yueming Zhou, Andras Csehi
Summary: The energy levels of atoms and molecules are distorted by dynamic Stark shift (DSS) when exposed to intense, short, high-frequency laser pulses. These level shifts are induced by the coupling with nonresonant states and follow the intensity profile of the laser pulse. The multiphoton ionization pathway is significantly modified by transient resonance suppressions and enhancements, resulting in clear fingerprints in the energy spectrum of emitted photoelectrons.
Article
Environmental Sciences
Nana Wu, Guannan Geng, Liu Yan, Jianzhao Bi, Yanshun Li, Dan Tong, Bo Zheng, Qiang Zhang
Summary: The study compares the city-level NO (x) emissions from a proxy-based emission inventory (MEIC) with a highly resolved emission inventory (MEIC-HR), indicating that the discrepancies in NO (x) emissions are influenced by the proportions of emissions from point sources and NO (x) emissions per industrial gross domestic product (IGDP). The use of IGDP as a spatial proxy may lead to overestimation of NO (x) emissions in cities with lower industrial emission intensities or less industrial facilities in the MEIC.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Chemistry, Physical
Haoyang Li, Guanyu Jiang, Menghui Jia, Simin Cao, Sanjun Zhang, Jinquan Chen, Haitao Sun, Jianhua Xu, Jay R. Knutson
Summary: The ultrafast Forster resonance energy transfer (FRET) between tyrosine and tryptophan in model peptides has been investigated using a femtosecond up-conversion spectrophotofluorometer. The study reveals the mechanism and rates of this energy transfer process and provides suggestions for protein ultrafast dynamics studies and complex FRET problems.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Anton Tamtoegl, Adrian Ruckhofer, Davide Campi, William Allison, Wolfgang E. Ernst
Summary: This article introduces the phenomenology of resonant scattering and discusses obtaining information about weak adsorption systems through experiments. Research compares experimental data for the He-Sb2Te3(111) system and recent results for topological semimetal and insulator surfaces, while also discussing the potential of calculating helium-surface interaction potentials.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Optics
M. Archimi, M. Ceccanti, M. Distefano, L. Di Virgilio, R. Franco, A. Greco, C. Simonelli, E. Arimondo, D. Ciampini, O. Morsch
Summary: Experimental measurements of blackbody-radiation-induced transitions between high-lying S, P, and D Rydberg levels of rubidium atoms showed significant deviations from theory, possibly due to a modified blackbody spectrum. Installing additional microwave cavities around the cell can be used to control and suppress these transitions.
Article
Optics
Igor L. Glukhov, Aleksandr A. Kamenski, Vitaly D. Ovsiannikov, Vitaly G. Palchikov
Summary: This research focuses on the measurement and calculation of microwave and radio-frequency radiation parameters based on the quantum-optical approach. The frequencies and matrix elements of transitions between Rydberg states are determined, and the approximation expressions provide accurate evaluation of these parameters.
Article
Environmental Sciences
Yanan Yi, Qing Li, Kun Zhang, Rui Li, Liumei Yang, Zhiqiang Liu, Xiaojuan Zhang, Shunyao Wang, Yangjun Wang, Hui Chen, Ling Huang, Jian Zhen Yu, Li Li
Summary: This study investigated the sources, health risks, and temporal variations of elemental composition in PM2.5 in urban Changzhou, China. Industrial emissions were identified as the main contributor to carcinogenic risk, highlighting the need for strict regulation of industrial sources.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Pragati Rai, Jay G. Slowik, Markus Furger, Imad El Haddad, Suzanne Visser, Yandong Tong, Atinderpal Singh, Guenther Wehrle, Varun Kumar, Anna K. Tobler, Deepika Bhattu, Liwei Wang, Dilip Ganguly, Neeraj Rastogi, Ru-Jin Huang, Jaroslaw Necki, Junji Cao, Sachchida N. Tripathi, Urs Baltensperger, Andre S. H. Prevot
Summary: The study presents highly time-resolved measurements of size-fractionated elements in Asian and European cities. The data shows higher elemental concentrations in Asian cities compared to European cities. Analysis of enrichment factors and size distribution allows for a rough classification of major elemental sources.
ATMOSPHERIC CHEMISTRY AND PHYSICS
(2021)
Article
Engineering, Environmental
Eva Y. Pfannerstill, Caleb Arata, Qindan Zhu, Benjamin C. Schulze, Roy Woods, Colin Harkins, Rebecca H. Schwantes, Brian C. Mcdonald, John H. Seinfeld, Anthony Bucholtz, Ronald C. Cohen, Allen H. Goldstein
Summary: Los Angeles is a major hotspot for air pollution, particularly ozone and particulate matter. Despite reductions in vehicular emissions, the improvement of ozone and PM2.5 levels in the region has been limited. Measurement of VOCs and comparison with emission inventories reveal discrepancies in the amount and distribution of observed VOC emissions in Los Angeles.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Mechanics
J. Haerter, D. S. Martinez, R. Poser, B. Weigand, G. Lamanna
Summary: This study verifies the assumptions of theoretical studies by using PIV to measure the velocity in two different porosity porous models at different Reynolds numbers. The results indicate that large-scale turbulent structures generated by the interaction with a turbulent outer flow exist and rapidly decay within the porous medium, validating closure models for volume-averaged computational studies.
Article
Spectroscopy
Jakub Slawski, Sebastian Szewczyk, Gotard Burdzinski, Krzysztof Gibasiewicz, Joanna Grzyb
Summary: Transient absorption spectroscopy was used to investigate the early photodynamics in a system of CdTe quantum dots (QDs) and cytochrome c (Cyt c) protein. About 25% of excited QD electrons in the QDs and Cyt c mixtures quickly relax to the ground state, while roughly 75% decay on a slower time scale, mainly due to quenching by Cyt c. Energy transfer is the primary quenching mechanism, but electron transfer also contributes significantly, resulting in photoreduction of Cyt c.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Physics, Multidisciplinary
J. Hertkorn, J-N Schmidt, F. Boettcher, M. Guo, M. Schmidt, K. S. H. Ng, S. D. Graham, H. P. Buechler, T. Langen, M. Zwierlein, T. Pfau
Summary: Experimental measurement of density fluctuations across the superfluid-supersolid phase transition provides insight into the static structure factor, spectrum of elementary excitations, and dominant fluctuation patterns. Strong response in static structure factor and presence of a distinct roton minimum in the dispersion relation suggest the presence of roton modes at the quantum critical point in the supersolid state. The study also indicates that the supersolid state supports both superfluid and crystal phonons.
Article
Physics, Multidisciplinary
J-N Schmidt, J. Hertkorn, M. Guo, F. Boettcher, M. Schmidt, K. S. H. Ng, S. D. Graham, T. Langen, M. Zwierlein, T. Pfau
Summary: By observing density fluctuations near a droplet crystallization transition in dipolar Bose-Einstein condensates, researchers were able to characterize radial and angular roton excitations and identify the crystallization mechanism. The fluctuations peak with increasing interaction strength, indicating the system's transition to a crystalline state. Comparisons with theoretically calculated excitation spectra provided insights into the softening of angular roton modes.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
J. Hertkorn, J-N Schmidt, M. Guo, F. Boettcher, P. Uerlings, H. R. Buechler, T. Langen, M. Zwierlein, T. Pfau
Summary: Through theoretical investigation, we found that spontaneous rotational symmetry breaking can lead to the emergence of a supersolid phase with characteristic collective excitations in specific regimes. Studying the dynamics across the transition, we demonstrate how these supersolids can be realized using standard protocols in state-of-the-art experiments.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Joana Fraxanet, Daniel Gonzalez-Cuadra, Tilman Pfau, Maciej Lewenstein, Tim Langen, Luca Barbiero
Summary: The study reveals the presence of localized edge states and gapless bulk excitations at topological quantum critical points in strongly correlated systems, explaining the separation of two distinct phases.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Nicolas Zuber, Viraatt S. V. Anasuri, Moritz Berngruber, Yi-Quan Zou, Florian Meinert, Robert Loew, Tilman Pfau
Summary: Researchers have discovered a new type of molecular ion based on the interaction between the ionic charge and a flipping-induced dipole of a highly excited electron, called Rydberg atom. This molecular ion has a bond length of several micrometres. Using a high-resolution ion microscope, they have measured the vibrational spectrum and spatially resolved the bond length and angular alignment of the molecule. Due to the large bond length, the molecular dynamics are extremely slow.
Article
Physics, Multidisciplinary
Florian Christaller, Max Maeusezahl, Felix Moumtsilis, Annika Belz, Harald Kuebler, Hadiseh Alaeian, Charles S. Adams, Robert Loew, Tilman Pfau
Summary: We investigate the generation of high atomic densities using light-induced atomic desorption in a vapor cell. By pulsing an intense off-resonant laser on a sapphire-coated cell, we observe the desorption of atomic clouds from the internal surfaces. Time-resolved absorption spectroscopy reveals the evolution of atomic density, showing broadening and line shift of the atomic resonances, which are attributed to dipole-dipole interactions. These findings highlight the potential of fast switching of atomic density and dipolar interactions for future quantum devices based on excitation blockade.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Yi-Quan Zou, Moritz Berngruber, Viraatt S. V. Anasuri, Nicolas Zuber, Florian Meinert, Robert Loew, Tilman Pfau
Summary: Vibrational dynamics in conventional molecules usually occur on a picosecond or shorter timescale. However, ultralong-range Rydberg molecules exhibit dramatically slowed down dynamics due to their large bond length of up to several micrometers. In this study, we directly observe the vibrational dynamics of a recently discovered Rydberg-atom-ion molecule. By applying a weak external electric field, we are able to control the molecule's orientation and induce vibrational dynamics. Our research opens up opportunities for controlling molecular dynamics in Rydberg molecules.
PHYSICAL REVIEW LETTERS
(2023)
Review
Physics, Multidisciplinary
Lauriane Chomaz, Igor Ferrier-Barbut, Francesca Ferlaino, Bruno Laburthe-Tolra, Benjamin L. Lev, Tilman Pfau
Summary: Since the achievement of quantum degeneracy in gases of chromium atoms in 2004, the experimental investigation of ultracold gases made of highly magnetic atoms has blossomed, yielding the observation of unprecedented phenomena. This review aims to present the unique aspects of the magnetic quantum-gas platform for exploring ultracold and quantum physics and give an overview of experimental achievements.
REPORTS ON PROGRESS IN PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Yannick Schellander, Marius Winter, Maurice Schamber, Fabian Munkes, Patrick Schalberger, Harald Kuebler, Tilman Pfau, Norbert Fruehauf
Summary: Real-time ultraviolet photodetectors are achieved using metal-semiconductor-metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) serves as the semiconductor material and gold as the metal electrodes. The readout of individual sensors is implemented through a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. Both the photosensor and the transimpedance amplifier are manufactured on glass substrates. The measured photosensor exhibits high responsivity R, low response time t(RES), and good noise equivalent power value NEP.
JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY
(2023)
Article
Physics, Multidisciplinary
Alice Pagano, Sebastian Weber, Daniel Jaschke, Tilman Pfau, Florian Meinert, Simone Montangero, Hans Peter Buechler
Summary: We study the implementation of a high-fidelity controlled-phase gate in a Rydberg quantum computer. By optimizing the pulse shapes, we are able to reduce the gate infidelity and analyze the influence of fundamental error sources in an experimentally realistic setup. The results show that achieving high gate fidelity is possible.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Physics, Multidisciplinary
A. Skljarow, H. Kuebler, C. S. Adams, T. Pfau, R. Loew, H. Alaeian
Summary: Strong light-induced interactions between atoms are crucial for quantum information processing. In a dielectric environment, the scattering and light-induced dipolar interaction of atoms can be enhanced. By combining the high densities achievable in thermal atomic vapors with efficient coupling to a slot waveguide, researchers have achieved controlled and enhanced atom interactions. The experimental results are in agreement with simulations, paving the way for robust and scalable quantum nonlinear optics and all-optical quantum information processing at room temperature.
PHYSICAL REVIEW RESEARCH
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Max Maeusezahl, Florian Christaller, Oliver de Vries, Marco Ploetner, Hao Zhang, Annika Belz, Benjamin Heinrich, Till Walbaum, Thomas Schreiber, Andreas Tuennermann, Harald Kuebler, Robert Loew, Tilman Pfau
Summary: The study introduces a highly specialized 1010 nm fiber amplifier developed for a novel parametric single-photon source, highlighting its importance in quantum-optical applications.
2021 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
(2021)
Article
Physics, Multidisciplinary
J. Hertkorn, J-N Schmidt, M. Guo, F. Boettcher, K. S. H. Ng, S. D. Graham, P. Uerlings, T. Langen, M. Zwierlein, T. Pfau
Summary: The study investigates the phase diagram of two-dimensional quantum ferrofluids formed from ultracold atoms in different trap geometries, revealing the dominance of two-dimensional supersolid crystals at low densities and the presence of honeycomb, labyrinthine states, and a pumpkin phase at higher densities. The research sheds light on the various patterns of quantum ferrofluids and demonstrates that their occurrence is common in strongly dipolar interacting systems stabilized by effects beyond mean-field.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Optics
Ioannis Caltzidis, Harald Kuebler, Tilman Pfau, Robert Loew, Mark A. Zentile
Summary: The atomic Faraday dichroic beam splitter separates signal and idler fields from pump degenerate four-wave mixing in an atomic source by rotating the plane of polarization of one mode 90° with respect to the other, achieving significant suppression and high transmission rates in the outputs. This technique eliminates the need for spatial separation of four-wave mixing modes and improves process efficiency in waveguide experiments.
Article
Optics
H. Alaeian, G. Giedke, I Carusotto, R. Loew, T. Pfau
Summary: This article theoretically investigates the first- and second-order quantum dissipative phase transitions of a three-mode cavity with a Hubbard interaction. By employing the Wigner function formalism, the study shows that quantum fluctuations notably limit the coherence time of the Goldstone mode. The theoretical predictions suggest that interacting multimode photonic systems are versatile test beds for investigating the crossovers between mean-field picture and quantum phase transitions.
