Article
Physics, Multidisciplinary
Yan-Mei Liu, Ya-Ning Li, Lei Zhang, Zhi-Hong Jiao, Song-Feng Zhao, Guo-Li Wang
Summary: In this work, we theoretically investigate the intensity and polarization characteristics of terahertz waves radiated by bi-elliptical polarized two-color laser fields with orthogonal or parallel major axes. Our simulations show that circularly polarized terahertz waves with comparable intensity to co-rotating CP or parallel LP laser field can be generated using a longer-wavelength few-cycle bi-elliptical field. Moreover, the dual-color elliptical field with tiny or large ellipticity can significantly improve THz energy and ellipticity compared to other laser field configurations.
FRONTIERS IN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Frieder Lindel, Edoardo G. Carnio, Stefan Yoshi Buhmann, Andreas Buchleitner
Summary: We adjust the quantum statistics of a bosonic field to deterministically manipulate a quantum system into a desired state. Accessible states of the field in experiments enable precise control of multilevel or multiqubit systems, even beyond the limitations of rotating-wave approximation. This extends optimal control theory to the domain of fully quantized and strongly coupled control and target degrees of freedom.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Elena V. Basiuk, Oleg V. Prezhdo, Vladimir A. Basiuk
Summary: Graphene is used in applications involving both infinite sheets and finite structures with edges and pores. The behavior of adsorption on graphene is usually rigid, except when adsorbing lanthanide atoms. Lanthanides can cause considerable distortion in finite size structures, and the level of distortion depends on the number of unpaired electrons. This distortion is tangible for graphene quantum dots and for atom adsorption closer to graphene edges.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Nanoscience & Nanotechnology
D. Khusyainov, T. Gareev, V. Radovskaia, K. Sampathkumar, S. Acharya, M. Siskins, S. Manas-Valero, B. A. Ivanov, E. Coronado, Th. Rasing, A. V. Kimel, D. Afanasiev
Summary: Using a time-resolved magneto-optical pump-probe technique, the ultrafast laser-induced dynamics of mutually correlated spins and lattice in CoPS3 were experimentally studied. It was found that the femtosecond laser pulse acted as an ultrafast heater and melted the antiferromagnetic order. The resonant pumping of the T-4(1g) ? T-4(2g) electronic transition in Co2+ ions effectively changed their orbital momentum and generated a coherent B-g phonon mode.
Article
Physics, Multidisciplinary
Carlo Kleine, Marc-Oliver Winghart, Zhuang-Yan Zhang, Maria Richter, Maria Ekimova, Sebastian Eckert, Marc J. J. Vrakking, Erik T. J. Nibbering, Arnaud Rouzee, Edward R. Grant
Summary: This study investigates the strong field ionization and fragmentation dynamics of N-2 using ultrafast nitrogen K-edge spectroscopy. The results show a remarkably low population of the A(2)Pi(u) state and nearly equal populations of the X-2 sigma(+)(g) and B-2 sigma(+)(u) states in N-2(+). In addition, the fragmentation of N-2(+) is attributed to significant collisional dynamics in the plasma.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Ahmed Ghalgaoui, Benjamin P. Fingerhut, Klaus Reimann, Thomas Elsaesser, Michael Woerner
Summary: The terahertz response of solvated electrons in liquid water was studied through nonlinear ultrafast pump-probe experiments. Free electrons were generated by high-field THz or near-infrared multiphoton excitation, with concentrations ranging from c(e) = 4 to 140 x 10(-6) moles/liter. The time-resolved change of the dielectric function shows pronounced oscillations persisting up to 30 ps, with frequencies increasing with electron concentration and being set by the local electric field.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
H. V. Ovcharenko, Z. A. Maizelis, S. S. Apostolov, V. A. Yampol'skii
Summary: This study examines the theoretical propagation of a terahertz Gaussian beam through a thin sample of layered superconductor. It reveals that the Josephson current between the superconducting layers enables beam focusing instead of divergence on the Rayleigh range. Furthermore, due to nonlinearity, the focal length and waist of the transmitted beam depend on the incident beam intensity, exhibiting nontrivial hysteresis behavior that can be observed in experiments with THz lasers.
Article
Multidisciplinary Sciences
Zhenya Zhang, Fumiya Sekiguchi, Takahiro Moriyama, Shunsuke C. Furuya, Masahiro Sato, Takuya Satoh, Yu Mukai, Koichiro Tanaka, Takafumi Yamamoto, Hiroshi Kageyama, Yoshihiko Kanemitsu, Hideki Hirori
Summary: The authors studied HoFeO3 crystal using multicycle THz magnetic pulses enhanced strongly by spiral-shaped microstructure. The observed Faraday ellipticity demonstrates second- and third-order harmonics of the magnetization oscillation and an asymmetric oscillation behavior. The ability to drive a spin system to state far from the equilibrium is indispensable for investigating spin structures of antiferromagnets and their functional nonlinearities for spintronics.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Yan-Fei Li, Yue-Yue Chen, Karen Z. Hatsagortsyan, Christoph H. Keitel
Summary: This study investigates the longitudinal polarization of an electron beam during the interaction with counterpropagating circularly polarized ultraintense laser pulses, taking into account the anomalous magnetic moment of the electron. It is found that despite the suppression of helicity transfer from laser photons to the electron beam in linear and nonlinear Compton scattering processes, helicity transfer can still occur through an intermediate step of electron radiative transverse polarization, followed by spin rotation induced by the anomalous magnetic moment of the electron. Monte Carlo simulations demonstrate the consequent helicity transfer and electron radial polarization in femtosecond timescale. The findings highlight the importance of the leading QED vertex correction to the electron anomalous magnetic moment in the polarization dynamics in ultrastrong laser fields.
PHYSICAL REVIEW LETTERS
(2022)
Article
Optics
Dejan B. Milosevic
Summary: It has been shown that utilizing extreme terahertz (THz) pulses to assist strong-laser-field ionization can significantly increase the electron yield and emitted photoelectron energy with a lower THz field intensity. The vector potential amplitude of the THz field, comparable to that of the laser field, is the key control parameter. Numerical results are obtained using the improved strong-field approximation, and a physical explanation is provided using quantum-orbit theory.
Article
Physics, Multidisciplinary
Zhiqiang Wang, Wei Quan, Xiaolei Hao, Jing Chen, Xiaojun Liu
Summary: In this study, we investigate the effect of the ellipticity on the excitation and ionization of noble gas atoms in strong laser fields. We use a semiclassical model to analyze the results at different intensities and wavelengths, considering or ignoring the nonadiabatic effect. Our findings reveal that the ratio between excitation and ionization yields shows an anomalous maximum at nonzero ellipticity when nonadiabatic effect is ignored, but this anomalous behavior disappears when nonadiabatic effect is considered. This can be attributed to the nonadiabatic corrections of instantaneous ionization rate and the initial photoelectron momentum distribution at the tunnel exit.
FRONTIERS IN PHYSICS
(2023)
Article
Physics, Multidisciplinary
Dejan B. B. Milosevic
Summary: Quantum-orbit theory is a powerful tool for understanding atomic processes in strong fields. This theory is especially useful for studying complex tailored fields that are difficult to calculate exactly. By applying this theory, we can describe high-order harmonic generation, high-order above-threshold ionization, and terahertz-pulse-assisted strong-field ionization, and gain new insights into the physics behind these phenomena. One interesting finding is that by adjusting the time delay between laser and terahertz pulses, we can extend the low-energy structures in photoelectron spectra to higher energies, allowing for better resolution.
EUROPEAN PHYSICAL JOURNAL PLUS
(2023)
Article
Physics, Multidisciplinary
Yu-Ning Yang, Su-Qi Chen, Zhao-Han Zhang, Hui Jiang, Min Chen, Yang Li, Feng He
Summary: This paper builds a model to explain the high harmonic generation in combined EUV and midinfrared laser fields. By embodying the spin-resolved three-electron dynamics, the model results agree with the time-dependent Schrodinger equation simulations including three active electrons. The intriguing picture explored in this work is fundamentally distinguished from scenarios relying on spin-orbit coupling.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Tao E. Li, Abraham Nitzan, Sharon Hammes-Schiffer, Joseph E. Subotnik
Summary: This study presents a quantum simulation of vibrational strong coupling in the collective regime using thermostated ring-polymer molecular dynamics. The simulation shows that including nuclear and photonic quantum effects does not change the Rabi splitting but broadens polaritonic line widths. Additionally, both quantum and classical simulations predict that the static dielectric constant of liquid water remains largely unchanged inside vs outside the cavity under thermal equilibrium. However, this disagrees with a recent experiment, suggesting potential limitations of the approach or unexplored experimental factors.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Optics
Hongqiang Xie, Hongbin Lei, Guihua Li, Jinping Yao, Qian Zhang, Xiaowei Wang, Jing Zhao, Zhiming Chen, Ya Cheng, Zengxiu Zhao
Summary: This study investigates the quantum emission properties of molecular ions, finding that collective emission behaviors can be readily observed in high-gain cases, while superradiant amplification is quenched in low-gain cases. Seed amplification and free induction decay play essential roles in the latter situation.
PHOTONICS RESEARCH
(2021)
Article
Chemistry, Physical
Fabio Novelli, Claudius Hoberg, Ellen M. Adams, J. Michael Klopf, Martina Havenith
Summary: The dynamical complexity of the hydrogen-bonded water network is studied through intense Terahertz spectroscopy, exploring anharmonicity effects and driving the liquid into the nonlinear response regime. By comparing experiments on static and free-flowing water samples, distinct contributions of thermal, acoustic, and nonlinear optical effects are disentangled. Anisotropic nonlinear optical response is observed during pump-probe overlap, with the nonlinear signal being more prominent in the liquid jet due to pronounced temperature and density perturbations.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Simone Pezzotti, Federico Sebastiani, Eliane P. van Dam, Sashary Ramos, Valeria Conti Nibali, Gerhard Schwaab, Martina Havenith
Summary: Hydration free energies are determined by the delicate balance between hydrophobic and hydrophilic interactions. A spectroscopic approach using THz spectroscopy allows direct access to the contributions of cavity formation and hydrophilic interactions, and enables the separate determination of the thermodynamic effects of hydrophobic and hydrophilic interactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Devendra Mani, Tarun Kumar Roy, Jai Khatri, Gerhard Schwaab, Sebastian Blach, Christoph Hoelzl, Harald Forbert, Dominik Marx, Martina Havenith
Summary: The application of external electric and magnetic fields is a powerful tool for controlling the alignment of molecules when thermal fluctuations are small. This study demonstrates that internal electric fields in a molecular cluster can also be used for such control. By utilizing the electric field of a single molecular dipole, researchers were able to manipulate the aggregation mechanism of subsequently added acetonitrile molecules. The presence of the internal electric field created by an HCl molecule resulted in the formation of exotic linear acetonitrile chains at 0.37K.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Review
Chemistry, Multidisciplinary
Hongxia Hao, Luis Ruiz Pestana, Jin Qian, Meili Liu, Qiang Xu, Teresa Head-Gordon
Summary: In this review, recent theoretical efforts in modeling interfaces and the understanding of transport and chemical transformations at air-liquid and solid-liquid interfaces are described.
WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Hongxia Hao, Ellen M. Adams, Sarah Funke, Gerhard Schwaab, Martina Havenith, Teresa Head-Gordon
Summary: Transport mechanisms of solvated protons in reverse micelles containing NaAOT or CTABr were studied using reactive force field simulations. The proton hopping events were found to be suppressed for NaAOT and completely ceased for CTABr. The sluggish proton dynamics in both charged reverse micelles were attributed to the expulsion of hydronium and chloride ions from the interface, resulting in increased pH of the acid pools compared to nonionic reverse micelles. The localized oscillatory hopping dominated in the charged micelles, especially for CTABr, where the proton residence time was significantly increased.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Luis Ruiz Pestana, Swathi Shantha Raju, Chaitanya Guntoorkar, Prannoy Suraneni
Summary: The dissolution of silicate and other oxide glasses is important in natural processes and technological applications. The role of heterogeneity in the dissolution kinetics of glass is not well understood, but it can either slow down or speed up the process depending on the extent of disorder. Phase-separated systems are governed by the less-soluble phase, while well-mixed systems can dissolve faster due to the sparse structure left behind by the more soluble phase.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Simone Pezzotti, Benedikt Koenig, Sashary Ramos, Gerhard Schwaab, Martina Havenith
Summary: Water actively participates in liquid-liquid phase separation (LLPS) by driving and being involved in the process. LLPS is governed by changes in hydration entropy and enthalpy. To tune LLPS for biological and medical applications, a general model is required to quantify thermodynamic driving forces. In this study, we develop such a model based on measured THz features of hydration populations, revealing the thermodynamic changes and providing a rational means to manipulate LLPS.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Multidisciplinary Sciences
Fabio Novelli, Kaixuan Chen, Adrian Buchmann, Thorsten Ockelmann, Claudius Hoberg, Teresa Head-Gordon, Martina Havenith
Summary: The study investigates the photo-induced radiolysis of water using an optical-pump terahertz-probe spectroscopy setup, revealing three distinct spectral responses. These responses correspond to the initial diffuse electron, the mass rearrangement of solvent molecules, and the weakening of the solvent cage characterized by the localized electron.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Multidisciplinary
Gilberto Garcia Del Angel, Jose A. Sainz-Aja, Pablo Tamayo, Ana Cimentada, Rene Cabrera, Luis Ruiz Pestana, Carlos Thomas
Summary: Modern society relies heavily on sand casting to manufacture metal components, resulting in a significant amount of waste known as Used Foundry Sand (UFS). Currently, UFS is mostly disposed of in landfills, causing economic and environmental issues. This study proposes the use of UFS as fine aggregates in concrete production and analyzes its effects on various properties of mortars. The results show that the incorporation of UFS decreases workability, affects physical and mechanical properties, and requires a higher water-to-cement ratio. Recommendations are made regarding the maximum replacement ratio and the consideration of water-to-cement ratio to balance workability and mechanical properties.
APPLIED SCIENCES-BASEL
(2023)
Article
Chemistry, Physical
Simon Schulke, Melinda Nolten, Gerhard Schwaab, Martina Havenith
Summary: This study demonstrates the potential of using Terahertz-FTIR spectroscopy as a label-free probe to measure the pH-dependent spectra of solvated amine compounds and correlate them with pKa values, thus allowing investigation of the charge state of biomolecules in water.
Article
Chemistry, Physical
Sampad Bag, Simone Pezzotti, Debasish Das Mahanta, Simon Schulke, Gerhard Schwaab, Martina Havenith
Summary: This study reports the THz measurement results of aqueous acetic acid solutions and explores the spectral characteristics of hydration motifs. By quantitatively correlating these changes to mixing entropy and enthalpy, a quantitative relationship between the balance of local hydrophobic and hydrophilic solvation motifs and macroscopic mixing thermodynamic properties is established.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
Thorsten Ockelmann, Claudius Hoberg, Adrian Buchmann, Fabio Novelli, Martina Havenith
Summary: This study investigates the energy dissipation mechanism in the hydrogen-bonded network of water upon photoexcitation of a photoacid, revealing that energy transfer occurs through acoustic phonon propagation. It is found that the propagation in the water network exhibits long-range correlation with a constant group velocity within the first 10 ps, followed by thermalization and a temperature increase of ΔT = 0.5 degrees C after 300 ps.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Multidisciplinary
Debasish Das Mahanta, Dennis Robinson Brown, Simone Pezzotti, Songi Han, Gerhard Schwaab, M. Scott Shell, Martina Havenith
Summary: Based on experimental and theoretical study, it is found that global thermodynamic mixing properties of glycerol and water are determined by local solvation structures. Three hydration water populations, including bulk water, bound water, and cavity wrap water, are identified. The study shows a 1:1 connection between the population of bound waters and the mixing enthalpy, which can be further confirmed by simulation results. This allows for rational design of polyol water and other aqueous mixtures to optimize technological applications.
Article
Chemistry, Multidisciplinary
Claudius Hoberg, Justin J. Talbot, James Shee, Thorsten Ockelmann, Debasish Das Mahanta, Fabio Novelli, Martin Head-Gordon, Martina Havenith
Summary: Photo-induced excited-state proton transfer (ESPT) reactions are important in biological and chemical processes. In this study, optical pump THz probe spectroscopy and molecular dynamics simulations were used to investigate solvation environment changes in different derivatives of pyranine. The results suggest efficient sub-ps energy transfer into a specific solvent mode, promoting proton transfer. Furthermore, damped oscillations in the THz signal indicated vibrational energy transfer between the photoexcited chromophore and solvent molecules.