Article
Multidisciplinary Sciences
Hong-Yi Lei, Fang-Zheng Sun, Tian-Ze Wang, Hao Chen, Dan Wang, Yan-Yu Wei, Jing-Long Ma, Guo-Qian Liao, Yu-Tong Li
Summary: This research focuses on the highly efficient production of millijoule-level terahertz pulses by irradiating the rear side of a metal foil with a 10-TW femtosecond laser pulse. By analyzing the terahertz and electron emission and conducting particle-in-cell simulations, the physical reasons for the efficient terahertz generation are discussed. The resulting focused terahertz electric field strength exceeding 2 GV/m is experimentally justified.
Article
Optics
Yu He, Haohan Shi, Nan Xue, Alexander Magunia, Shaohua Sun, Jingjie Ding, Bitao Hu, Zuoye Liu
Summary: This theoretical study investigates the excitation and manipulation of a two-level system with ultrashort intense extreme-ultraviolet laser fields. The focus is on the dynamical phase excursion of the energy states during the interaction and the resulting spectral modifications. The analysis includes fitting absorption line shapes using the Fano profile, quantifying the asymmetry parameter and dipole phase offset, and employing nonperturbative analytical calculations to understand the dependence of the dipole phase shift on the external field. The validity of the formulas is confirmed by comparing their predictions with numerical results.
Article
Optics
Paul Hickson, Joschua Hellemeier, Rui Yang
Summary: Adaptive optics is crucial for ground-based optical and infrared astronomy, offering high angular resolution and sensitivity. Systems using laser guide stars have high sky coverage potential, but are limited by return flux availability. Amplified spontaneous emission has the potential to enhance beacon intensity, but requires a thick population inversion in an electronically dense transition, with atomic oxygen and nitrogen being potential candidates.
Article
Physics, Multidisciplinary
K. Jiang, T. W. Huang, C. N. Wu, M. Y. Yu, H. Zhang, S. Z. Wu, H. B. Zhuo, A. Pukhov, C. T. Zhou, S. C. Ruan
Summary: Branched flow is a linear phenomenon that usually does not alter the properties of the medium. However, it has recently been discovered that nonlinear light branching can occur in the case of an intense laser propagating through a randomly uneven medium. The observed branching pattern depends on the laser intensity and differs from the existing linear ones. The nonlinear branched propagation of intense lasers potentially opens up a new area for laser-matter interaction and may be relevant to other branching phenomena of a nonlinear nature.
MATTER AND RADIATION AT EXTREMES
(2023)
Article
Multidisciplinary Sciences
Amit D. Lad, Y. Mishima, Prashant Kumar Singh, Boyuan Li, Amitava Adak, Gourab Chatterjee, P. Brijesh, Malay Dalui, M. Inoue, J. Jha, Sheroy Tata, M. Trivikram, M. Krishnamurthy, Min Chen, Z. M. Sheng, K. A. Tanaka, G. Ravindra Kumar, H. Habara
Summary: This study demonstrates the generation of bright, energetic, and directional electron bunches by efficiently transferring energy from high contrast laser pulses to grating targets under surface plasmon resonance (SPR) conditions. The surface plasmon excited grating target enhances the electron flux and temperature. Particle-in-Cell simulations explain the emission of fast electrons in different directions during laser interaction.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Fluids & Plasmas
G. E. Cochran, A. J. Kemp, S. C. Wilks, S. M. Kerr, G. J. Williams, D. A. Alessi, J-M G. Di Nicola, M. R. Hermann, D. H. Kalantar, T. E. Lanier, M. M. Marinak, D. Martinez, M. A. Prantil, C. Widmayer, W. H. Williams, A. J. Mackinnon
Summary: Compound parabolic concentrator (CPC) cone targets can increase MeV photon production, but spatial wings of the beam may interfere with neighboring targets' preformed plasma. Assessing this interaction is crucial for optimizing laser performance.
PHYSICS OF PLASMAS
(2021)
Article
Physics, Multidisciplinary
Franz E. Haniel, Hartmut Schroeder, Subhendu Kahaly, Arjun Nayak, Mathieu Dumergue, Sudipta Mondal, Filus Zoltan, Roland Flender, Mate Kurucz, Ludovit Haizer, Balint Kiss, Dimitris Charalambidis, Matthias F. Kling, Paraskevas Tzallas, Boris Bergues
Summary: The experimental study investigates the double ionization of xenon and krypton under intense four-cycle pulses, revealing significant saturation of double ionization at intensities close to 1.2 x 10(14) W cm(-2). The yield ratio of doubly to singly charged xenon is about 75%, while for krypton it is 25%. Additionally, the Perelomov-Popov-Terentyev theory underestimates the observed double ionization yield in the deeply saturated regime of the experiment.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Physical
M. Zukerstein, J. Hrabovsky, J. Sladek, I Mirza, Y. Levy, N. M. Bulgakova
Summary: Tubular structures and microneedles can be formed on monocrystalline silicon surface using ultrashort laser pulses. The height and morphology of the structures can be controlled by single and multi-pulsed irradiation, and the mechanisms responsible for their formation are discussed. The generated silicon microtubes and needles have applications in various fields.
APPLIED SURFACE SCIENCE
(2022)
Article
Optics
Arnab Sen, S. Mandal, Sanket Sen, Bhas Bapat, R. Gopal, V Sharma
Summary: In this study, we investigated the fragmentation of multiply charged CH3I ions induced by moderately intense ultrashort laser fields. The results show an increase in fragment yield with longer pulse durations. Analysis based on theoretical models suggests that enhanced ionization is a result of rearrangement of molecular orbitals leading to increased resonance multiorbital coupling at critical distances.
Article
Physics, Multidisciplinary
Y. Cao, L. X. Hu, D. B. Zou, X. H. Yang, Y. T. Hu, J. Zhao, Y. Lu, Y. Yin, F. Q. Shao, T. P. Yu
Summary: This paper proposes a novel method to manipulate positrons using a specific laser structure, enabling the capture, collimation, compression, and acceleration of positrons. High-quality positron bunches with improved features are obtained.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
M. B. Peters, V. P. Majety, A. Emmanouilidou
Summary: A three-dimensional semiclassical model was developed to study three-electron escape dynamics in a strongly driven linear triatomic molecule, HeH2+. The study found weak electronic correlation in frustrated triple ionization and observed that the molecule deviates from its initial linear configuration during fragmentation.
Article
Chemistry, Analytical
Daniel Holder, Rudolf Weber, Thomas Graf
Summary: The analytical model predicts the progress and final depth of laser micromachining of grooves in metals with ultrashort laser pulses by recursively calculating the depth increments induced by successive scans of the laser beam along the groove. Experimental validation confirms the model and its assumptions for micromachining of grooves in a Ti-alloy with femtosecond pulses and various parameters.
Article
Optics
R. Piccoli, J. M. Brown, Y-G Jeong, A. Rovere, L. Zanotto, M. B. Gaarde, F. Legare, A. Couairon, J. C. Travers, R. Morandotti, B. E. Schmidt, L. Razzari
Summary: The article discusses a technology for pulse compression using hollow-core fibers and identifies an unexplored mechanism for generating visible-light pulses with few cycles. Using a commercial ytterbium laser, they successfully convert few-hundred-femtosecond-long infrared pulses into single-cycle visible light pulses.
Article
Chemistry, Physical
Kenta Nakamura, Shinichi Fukahori, Hirokazu Hasegawa
Summary: The rotational dynamics of NO in the electronic ground X-2 pi state is numerically investigated using an intense two-color laser field, with different pulse durations leading to either rotational Raman excitation or suppression of rotational excitation. In addition, transitions between lambda-type doubling are induced, with the generation of a coherent wave packet between lambda-type doubling in J = 0.5 at a specific pulse duration. The alternation of the rotational direction of the electron around the N-O axis is proposed to be observed experimentally.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Physics, Applied
Eva Diaz, Alberto Anadon, Martina Morassi, Michel Hehn, Aristide Lemaitre, Jon Gorchon
Summary: This work focuses on the full characterization of terahertz pulses confined in waveguides. Terahertz photoconductive switch detectors were fabricated and used to sample the electrical pulses. Two calibration methods were developed to accurately characterize the pulse amplitude. These techniques provide a reliable tool to explore nonlinear phenomena at high THz intensities.
APPLIED PHYSICS LETTERS
(2023)
