Article
Optics
Zhiyong Qin, Changhai Yu, Jiansheng Liu, Zhijun Zhang, Shiyi Zhou, Zibo Xu, Jintan Cai, Xuhui Jiao, Zhongtao Xiang
Summary: We propose an efficient method for generating macroscopic high-order harmonics with a smooth broadband continuous spectrum structure using a temporal asymmetric laser field. The study shows that the selected continuous high-order harmonic spectra can support isolated attosecond pulses in the extreme ultraviolet region. Analysis reveals that the smooth broadband continuous spectrum is dominated by long-trajectory electron emissions.
Article
Physics, Multidisciplinary
Karim Achouri, Andrei Kiselev, Olivier J. F. Martin
Summary: We present a frequency-domain modeling technique for second-order nonlinear metasurfaces, derived from the generalized sheet transition conditions (GSTCs). By extending the GSTCs to include effective nonlinear polarizations, the effective nonlinear susceptibilities of a given metasurface can be retrieved and its nonlinear scattering responses can be predicted under arbitrary illumination conditions. The proposed model can serve as a design platform for implementing complex nonlinear metasurface based applications.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Yoonsoo Rho, SeokJae Yoo, Daniel B. Durham, DongJun Kang, Andrew M. Minor, Costas P. Grigoropoulos
Summary: Nonlinear optical response is a useful tool for studying the properties of materials, but its weak signal and limited reach make it difficult to probe deep-subwavelength-scale nonlinear optics. In this study, we propose a new method using an SHG-active plasmonic nanotip to achieve efficient second harmonic generation (SHG) nanoscopy. Our simulations suggest that enhancing the nonlinear response of the sample or suppressing the tip's response can lead to a high near-field SHG contrast, providing evidence of quantum mechanical nonlinear energy transfer. Furthermore, this technique can be used to study nanoscale corrosion and other physicochemical phenomena.
Article
Optics
Wenqing Li, Xiaosong Zhu, Pengfei Lan, Peixiang Lu
Summary: This paper revisits high-order harmonic generation (HHG) in high optical chirality corotating bicircular fields and extends the study to a frequency ratio higher than 1:2. By analyzing the classical trajectories, it is shown that the hindering effect of the Coriolis force on HHG decreases with the frequency ratio. Based on these findings, a method for producing highly elliptically polarized attosecond pulses using the corotating bicircular field with a frequency ratio of 1:3 is proposed. A comparison with extensively studied counter-rotating configurations is also made, and the results demonstrate the validity and superiority of the corotating configurations in terms of higher ellipticity and yield of generated attosecond pulses.
Article
Optics
Vyacheslav A. Trofimov, Dmitry M. Kharitonov, Mikhail Fedotov
Summary: This paper proposes a new scheme for fifth harmonic generation based on cascading third harmonic generation, which can improve frequency up-conversion efficiency. The feasibility of this scheme is theoretically demonstrated using multi-scale approach and can be applied directly to femtosecond pulses in a medium with cubic nonlinear response.
OPTICS AND LASER TECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Yudong Yang, Roland E. Mainz, Giulio Maria Rossi, Fabian Scheiba, Miguel A. Silva-Toledo, Phillip D. Keathley, Giovanni Cirmi, Franz X. Kartner
Summary: Attosecond science can reveal fundamental electronic dynamics in matter by improving spectral tunability and increasing photon flux in high-order harmonic sources. Parametric waveform synthesis enables the generation of highly-tunable isolated attosecond pulses, with central energy, spectral bandwidth/shape, and temporal duration controlled by shaping laser waveforms through relative-phase and carrier-envelope phase parameters. This advancement not only expands experimental possibilities in attosecond science, but also demonstrates coherent strong-field control of free-electron trajectories using tailored optical waveforms.
NATURE COMMUNICATIONS
(2021)
Article
Optics
Ahmad Reza Madhani, Elnaz Irani, Mohammad Monfared
Summary: This paper theoretically investigates the generation of isolated elliptically polarized attosecond pulses from the interaction of Cl2 molecule and a polarization-gating laser pulse. Two methods are proposed, one using a single-color laser and controlling the molecule orientation angle, and the other using a two-color laser and adjusting the intensity ratio. The achieved attosecond pulses have different ellipticities and pulse durations.
Article
Optics
Marc Jankowski, Carsten Langrock, Boris Desiatov, Marko Loncar, M. M. Fejer
Summary: We propose a new approach to supercontinuum generation and carrier-envelope-offset detection based on saturated second-order nonlinear interactions in dispersion-engineered nanowaveguides. The technique developed here broadens the interacting harmonics by forming stable bifurcations of the pulse envelopes due to an interplay between phase-mismatch and pump depletion. The scaling laws suggest that future realization based on this approach could enable supercontinuum generation with orders of magnitude less energy than current state-of-the-art devices.
Article
Optics
Zelin Hao, Wenwei Liu, Zhancheng Li, Zhi Li, Guangzhou Geng, Yanchun Wang, Hua Cheng, Hammad Ahmed, Xianzhong Chen, Junjie Li, Jianguo Tian, Shuqi Chen
Summary: Metasurfaces have shown great potential in optical wave manipulation but face challenges in multidimensional manipulation of harmonic waves generated by nonlinear metasurfaces. This study presents an efficient design strategy based on the hydrodynamic model of free electron dynamics, allowing for full complex-amplitude modulation of second harmonic generation. The proposed nonlinear metasurfaces demonstrate spin-selective SHG optical vortices with independent topological charges, opening up new possibilities for nonlinear metasurface applications in optical information and multifunctional integration.
LASER & PHOTONICS REVIEWS
(2021)
Article
Optics
V. A. Birulia, M. A. Khokhlova, V. V. Strelkov
Summary: This study investigates the attosecond properties of coherent extreme ultraviolet (XUV) generated via high-order frequency mixing (HFM) through theoretical and numerical analysis. The research finds that the duration and carrier-envelope phase of the attosecond pulses generated by HFM can be effectively controlled, especially when one of the generating fields has much lower frequency and intensity compared to the other.
Article
Chemistry, Multidisciplinary
Rebeca Tudor, George Andrei Bulzan, Mihai Kusko, Cristian Kusko, Viorel Avramescu, Dan Vasilache, Raluca Gavrila
Summary: This paper proposes an efficient method to generate high-order Bessel-Gauss beams with orbital angular momentum (OAM) using a thin and compact optical element such as a multilevel spiral axicon. This approach provides a diffraction-free alternative to complex methods for OAM beam generation. The fabrication process for axicons with 16 and 32 levels is presented, which exhibit high mode conversion efficiency and good transmission for visible light. The Bessel vortex states generated by the proposed diffractive optical elements (DOEs) can be utilized for optical and quantum communication in free-space channels or optical fibers.
Article
Computer Science, Interdisciplinary Applications
Jose Miguel Pablos-Marin, Javier Serrano, Carlos Hernandez-Garcia
Summary: Artificial intelligence and deep learning are powerful tools for accessing complex simulations in intense ultrafast laser science. The use of neural networks to infer the microscopic high-order harmonic generation response allows for accurate and fast computation of extreme-ultraviolet/x-ray attosecond pulse generation. This method is especially suitable for macroscopic high-order harmonic generation driven by structured laser beams carrying orbital angular momentum.
COMPUTER PHYSICS COMMUNICATIONS
(2023)
Article
Optics
Chunyang Zhai, Xiaosong Zhu, Jie Long, Renzhi Shao, Yinfu Zhang, Lixin He, Qingbin Tang, Yingbin Li, Pengfei Lan, Benhai Yu, Peixiang Lu
Summary: A scheme to generate elliptically polarized attosecond pulses with mixed gases is proposed and theoretically demonstrated. The large ellipticity of high-order harmonics from the mixture can be tuned by controlling the mixing ratio and molecular alignment angle, and the polarization control is independent of temporal profile manipulation.
Article
Materials Science, Multidisciplinary
Tingting Liu, Xinyuan Fang, Shuyuan Xiao
Summary: Engineering nonlinear optical processes in dielectric nanostructures using chalcogenide phase-change material allows for efficient tuning of second-harmonic generation processes. The nonlinear SHG signal from nanoantennas can be enhanced and modulated by optically induced Mie-type resonances and the amorphous-to-crystalline phase change in GST. By adjusting the refractive index of GST, a maximum modulation depth of up to 540% is demonstrated, showing the potential for control of optical nonlinearity and smart designing of tunable nonlinear optical devices.
Article
Mathematics
Yernat M. Assylbekov, Ting Zhou
Summary: In this paper, an inverse boundary value problem of electromagnetism with nonlinear Second Harmonic Generation (SHG) process is considered. The unique determination of the electromagnetic material parameters and the SHG susceptibility parameter of the medium is shown by making electromagnetic measurements on the boundary. The case of interest is when a frequency is fixed.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Optics
Marcus Seidel, Federico Pressacco, Oender Akcaalan, Thomas Binhammer, John Darvill, Nagitha Ekanayake, Maik Frede, Uwe Grosse-Wortmann, Michael Heber, Christoph M. Heyl, Dmytro Kutnyakhov, Chen Li, Christian Mohr, Jost Mueller, Oliver Puncken, Harald Redlin, Nora Schirmel, Sebastian Schulz, Angad Swiderski, Hamed Tavakol, Henrik Tuennermann, Caterina Vidoli, Lukas Wenthaus, Nils Wind, Lutz Winkelmann, Bastian Manschwetus, Ingmar Hartl
Summary: The study reports a novel FEL facility laser that combines high average power output and pulse compression for studying ultrafast processes. Compared to other lasers, this new system has improved noise figures, compactness, simplicity, and power efficiency. It provides high-energy, short-duration pulses that can be adjusted through computer control.
LASER & PHOTONICS REVIEWS
(2022)
Article
Optics
Christoph M. Heyl, Marcus Seidel, Esmerando Escoto, Arthur Schoenberg, Stefanos Carlstroem, Gunnar Arisholm, Tino Lang, Ingmar Hartl
Summary: The article discusses the potential advantages of multi-pass cells (MPCs) in spectral broadening and post-compression applications. It introduces a novel energy scaling method using a bow tie geometry for MPCs. Numerical simulations demonstrate the successful compression of high-energy, long pulses into shorter pulses, and suggest possible routes for extending the method to higher energy levels.
JOURNAL OF PHYSICS-PHOTONICS
(2022)
Article
Optics
Esmerando Escoto, Anne-Lise Viotti, Skirmantas Alisauskas, Henrik Tunnermann, Ingmar Hartl, Christoph M. Heyl
Summary: Post-compression of ultra-short laser pulses via self-phase modulation can generate laser pulses with optical bandwidths exceeding the laser gain limitations. However, the compressed pulses usually suffer from temporal quality degradation. By managing dispersion and cascading the compression process, the impact of this effect can be limited, providing opportunities for new femtosecond laser architectures based on post-compressed picosecond or nanosecond laser systems.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2022)
Article
Optics
Ivan Sytcevich, Anne-Lise Viotti, Chen Guo, Jan Vogelsang, Fabian Langer, Anne L'Huillier, Cord L. Arnold
Summary: This article presents a compact and stable short-wave infrared light source capable of delivering few-cycle pulses with a wavelength of around 2 µm and a repetition rate of 200 kHz, with carrier-envelope phase stability. The potential of the system for driving strong-field experiments is demonstrated through high-order harmonic generation.
Article
Optics
David Busto, Hugo Laurell, Daniel Finkelstein-Shapiro, Christiana Alexandridi, Marcus Isinger, Saikat Nandi, Richard J. Squibb, Margherita Turconi, Shiyang Zhong, Cord L. Arnold, Raimund Feifel, Mathieu Gisselbrecht, Pascal Salieres, Tonu Pullerits, Fernando Martin, Luca Argenti, Anne L'Huillier
Summary: Quantum coherence is crucial in the study of ultrafast dynamics in matter, but in the case of photoionization, entanglement causes decoherence. This study investigates the decoherence resulting from the entanglement of the radial and angular degrees of freedom of the photoelectron. It is shown through experiment and theory that the strong dipole coupling between the 2s2p and 2p(2) states in He leads to entanglement and subsequent loss of coherence in angle-integrated measurements during autoionization.
EUROPEAN PHYSICAL JOURNAL D
(2022)
Article
Optics
Ann-Kathrin Raab, Marcus Seidel, Chen Guo, Ivan Sytcevich, Gunnar Arisholm, Anne L'Huillier, Cord l. Arnold, Anne-Lise Viotti
Summary: This study demonstrates the compression of the output of a 200 kHz, 34 W, 300 fs ytterbium amplifier to 31 fs, achieving a peak power of 2.5 GW with over 88% efficiency. Despite operating 80 times above the critical power for self-focusing in bulk material, the setup maintains excellent preservation of the input beam quality. Extensive characterizations indicate that the compressed pulses have promising applications in high harmonic generation and nonlinear optics in gases or solids.
Article
Multidisciplinary Sciences
Jasper Peschel, David Busto, Marius Plach, Mattias Bertolino, Maria Hoflund, Sylvain Maclot, Jimmy Vinbladh, Hampus Wikmark, Felipe Zapata, Eva Lindroth, Mathieu Gisselbrecht, Jan Marcus Dahlstroem, Anne L'Huillier, Per Eng-Johnsson
Summary: Understanding the ultrafast dynamics of photoionization requires characterizing all underlying ionization channels. In this study, the authors use an interferometry technique based on attosecond pulses to measure the phase and amplitude of individual angular momentum channels in the photoionization of neon.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Multidisciplinary
L. Neoricic, D. Busto, H. Laurell, R. Weissenbilder, M. Ammitzboell, S. Luo, J. Peschel, H. Wikmark, J. Lahl, S. Maclot, R. J. Squibb, S. Zhong, P. Eng-Johnsson, C. L. Arnold, R. Feifel, M. Gisselbrecht, E. Lindroth, A. L'Huillier
Summary: We studied the resonant two-photon ionization of helium atoms and measured the phase of the photoelectron wavepackets using an attosecond interferometric technique. Experiments were performed with angular and high energy resolution. The results were compared to calculations and an interpretation was given for the observed phase jumps at and away from resonance as well as their dependence on the emission angle.
FRONTIERS IN PHYSICS
(2022)
Article
Optics
Prannay Balla, Henrik Tuennermann, Sarper H. Salman, Mingqi Fan, Skirmantas Alisauskas, Ingmar Hartl, Christoph M. Heyl
Summary: The serrodyne principle is used to frequency shift electromagnetic signals by applying a linear phase ramp in the time domain. This technique is applied to high-power femtosecond laser pulses to shift the central wavelength over a range of several terahertz. Experimental results show successful wavelength shifting of a 75 W frequency comb laser from 1,030 nm to 1,060 nm and 1,000 nm, while maintaining coherence characteristics at the few hertz-level. This technique allows efficient wavelength conversion beyond the gain bandwidth of available laser platforms.
Article
Physics, Multidisciplinary
K. Veyrinas, M. Plach, J. Peschel, M. Hoflund, F. Catoire, C. Valentin, P. Smorenburg, H. Dacasa, S. Maclot, C. Guo, H. Wikmark, A. Zair, V Strelkov, C. Picot, C. Arnold, P. Eng-Johnsson, A. L'Huillier, E. Mevel, E. Constant
Summary: Attosecond pulses created by high-order harmonic generation in gases often exhibit strong chromatic aberrations. By spatially shaping the fundamental beam, the chromatic aberrations can be reduced, resulting in decreased variation of the XUV spectrum and improved longitudinal sensitivity of the focused attosecond pulses.
NEW JOURNAL OF PHYSICS
(2023)
Article
Optics
Anne-Lise Viotti, Chen Li, Gunnar Arisholm, Lutz Winkelmann, Ingmar Hartl, Christoph M. Heyl, Marcus Seidel
Summary: To meet the energy requirements of photon-hungry applications, researchers have developed a method to compress laser pulses, transforming a 0.1 GW peak power, picosecond laser into a 2.9 GW peak power, 8.2 fs ultra-short laser pulse. This compression method achieves a 120-fold pulse duration reduction, opening up possibilities for compact, efficient, and high repetition rate attosecond laser sources.
Article
Optics
Arthur Schoenberg, Haydar Sarper Salman, Ayhan Tajalli, Sonu Kumar, Ingmar Hartl, Christoph M. Heyl
Summary: The generation of below-threshold harmonics in gas-jets offers a promising route to optical frequency combs in the vacuum ultra-violet (VUV) range. Of particular interest is the 150 nm region, which can be used to probe the nuclear isomeric transition of the Thorium-229 isotope. Using readily available high-power, high-repetition-rate Ytterbium-based lasers, VUV frequency combs can be generated through below-threshold harmonic generation, specifically the 7th harmonic of 1030 nm. Understanding the achievable efficiencies of this process is crucial for the development of suitable VUV sources.
Article
Optics
L. A. U. R. A. Silletti, A. M. M. A. R. B. I. N. Wahid, E. S. M. E. R. A. N. D. O. Escoto, P. R. A. N. N. A. Y. Balla, S. U. P. R. I. Y. A. Rajhans, K. A. T. I. N. K. A. Horn, L. U. T. Z. Winkelmann, V. I. N. C. E. N. T. Wanie, A. N. D. R. E. A. Trabattoni, Christoph m. Heyl, F. R. A. N. C. E. S. C. A. Calegari
Summary: To overcome limitations in post-compression methods for ultrafast laser pulses, researchers utilize direct dispersion control in a gas-filled multi-pass cell, achieving single-stage post-compression of 150 fs pulses and up to 250 μJ pulse energy. Dispersion-engineered dielectric cavity mirrors enable nonlinear spectral broadening at 98% throughput, opening a route for compressing ytterbium lasers into the few-cycle regime.
Review
Physics, Applied
R. Weissenbilder, S. Carlstrom, L. Rego, C. Guo, C. M. Heyl, P. Smorenburg, E. Constant, C. L. Arnold, A. L'Huillier
Summary: This article reviews the physics of high-order harmonic generation (HHG) in gases, focusing on the macroscopic aspects of the nonlinear interaction, and discusses the influence of medium length, pressure, and driving laser intensity on HHG conversion efficiency. Efficient HHG can be achieved over a wide range of pressures and medium lengths if certain hyperbolic equations are met, providing design guidance for future high-flux XUV sources.
NATURE REVIEWS PHYSICS
(2022)
Article
Physics, Multidisciplinary
H. Laurell, D. Finkelstein-Shapiro, C. Dittel, C. Guo, R. Demjaha, M. Ammitzboll, R. Weissenbilder, L. Neoricic, S. Luo, M. Gisselbrecht, C. L. Arnold, A. Buchleitner, T. Pullerits, A. L'Huillier, D. Busto
Summary: We propose a protocol for continuous variable quantum state tomography of electrons resulting from the ionization of atoms or molecules by absorbing extreme ultraviolet light pulses. The protocol is validated through direct calculations of the quantum state of photoelectrons ejected from helium and argon near a Fano resonance. Additionally, ion-photoelectron entanglement due to spin-orbit splitting is distilled, enabling the investigation of quantum coherence and entanglement properties on ultrafast timescales.
PHYSICAL REVIEW RESEARCH
(2022)
