1
|
Woźniak AP, Adamowicz L, Pedersen TB, Kvaal S. Gaussians for Electronic and Rovibrational Quantum Dynamics. J Phys Chem A 2024; 128:3659-3671. [PMID: 38687971 PMCID: PMC11089519 DOI: 10.1021/acs.jpca.4c00364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 03/23/2024] [Accepted: 04/08/2024] [Indexed: 05/02/2024]
Abstract
The assumptions underpinning the adiabatic Born-Oppenheimer (BO) approximation are broken for molecules interacting with attosecond laser pulses, which generate complicated coupled electronic-nuclear wave packets that generally will have components of electronic and dissociation continua as well as bound-state contributions. The conceptually most straightforward way to overcome this challenge is to treat the electronic and nuclear degrees of freedom on equal quantum-mechanical footing by not invoking the BO approximation at all. Explicitly correlated Gaussian (ECG) basis functions have proved successful for non-BO calculations of stationary molecular states and energies, reproducing rovibrational absorption spectra with very high accuracy. In this Article, we present a proof-of-principle study of the ability of fully flexible ECGs (FFECGs) to capture the intricate electronic and rovibrational dynamics generated by short, high-intensity laser pulses. By fitting linear combinations of FFECGs to accurate wave function histories obtained on a large real-space grid for a regularized 2D model of the hydrogen atom and for the 2D Morse potential, we demonstrate that FFECGs provide a very compact description of laser-driven electronic and rovibrational dynamics.
Collapse
Affiliation(s)
| | - Ludwik Adamowicz
- Department
of Chemistry and Biochemistry, University
of Arizona, 1306 E University Blvd, Tucson, Arizona 85721-0041, United States
| | - Thomas Bondo Pedersen
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| | - Simen Kvaal
- Hylleraas
Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway
| |
Collapse
|
2
|
Galán MF, Serrano J, Jarque EC, Borrego-Varillas R, Lucchini M, Reduzzi M, Nisoli M, Brahms C, Travers JC, Hernández-García C, San Roman J. Robust Isolated Attosecond Pulse Generation with Self-Compressed Subcycle Drivers from Hollow Capillary Fibers. ACS PHOTONICS 2024; 11:1673-1683. [PMID: 38645995 PMCID: PMC11027177 DOI: 10.1021/acsphotonics.3c01897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/05/2024] [Accepted: 03/05/2024] [Indexed: 04/23/2024]
Abstract
High-order harmonic generation (HHG) arising from the nonperturbative interaction of intense light fields with matter constitutes a well-established tabletop source of coherent extreme-ultraviolet and soft X-ray radiation, which is typically emitted as attosecond pulse trains. However, ultrafast applications increasingly demand isolated attosecond pulses (IAPs), which offer great promise for advancing precision control of electron dynamics. Yet, the direct generation of IAPs typically requires the synthesis of near-single-cycle intense driving fields, which is technologically challenging. In this work, we theoretically demonstrate a novel scheme for the straightforward and compact generation of IAPs from multicycle infrared drivers using hollow capillary fibers (HCFs). Starting from a standard, intense multicycle infrared pulse, a light transient is generated by extreme soliton self-compression in a HCF with decreasing pressure and is subsequently used to drive HHG in a gas target. Owing to the subcycle confinement of the HHG process, high-contrast IAPs are continuously emitted almost independently of the carrier-envelope phase (CEP) of the optimally self-compressed drivers. This results in a CEP-robust scheme which is also stable under macroscopic propagation of the high harmonics in a gas target. Our results open the way to a new generation of integrated all-fiber IAP sources, overcoming the efficiency limitations of usual gating techniques for multicycle drivers.
Collapse
Affiliation(s)
- Marina Fernández Galán
- Grupo
de Investigación en Aplicaciones del Láser y Fotónica,
Departamento de Física Aplicada, Universidad de Salamanca, Salamanca, 37008, Spain
- Unidad
de Excelencia en Luz y Materia Estructuradas (LUMES), Universidad de Salamanca, Salamanca, 37008, Spain
| | - Javier Serrano
- Grupo
de Investigación en Aplicaciones del Láser y Fotónica,
Departamento de Física Aplicada, Universidad de Salamanca, Salamanca, 37008, Spain
- Unidad
de Excelencia en Luz y Materia Estructuradas (LUMES), Universidad de Salamanca, Salamanca, 37008, Spain
| | - Enrique Conejero Jarque
- Grupo
de Investigación en Aplicaciones del Láser y Fotónica,
Departamento de Física Aplicada, Universidad de Salamanca, Salamanca, 37008, Spain
- Unidad
de Excelencia en Luz y Materia Estructuradas (LUMES), Universidad de Salamanca, Salamanca, 37008, Spain
| | - Rocío Borrego-Varillas
- Institute
for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, Milano, 20133, Italy
| | - Matteo Lucchini
- Institute
for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, Milano, 20133, Italy
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milano, 20133, Italy
| | - Maurizio Reduzzi
- Institute
for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, Milano, 20133, Italy
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milano, 20133, Italy
| | - Mauro Nisoli
- Institute
for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, Milano, 20133, Italy
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milano, 20133, Italy
| | - Christian Brahms
- School
of Engineering and Physical Sciences, Heriot-Watt
University, Edinburgh, EH14 4AS, United
Kingdom
| | - John C. Travers
- School
of Engineering and Physical Sciences, Heriot-Watt
University, Edinburgh, EH14 4AS, United
Kingdom
| | - Carlos Hernández-García
- Grupo
de Investigación en Aplicaciones del Láser y Fotónica,
Departamento de Física Aplicada, Universidad de Salamanca, Salamanca, 37008, Spain
- Unidad
de Excelencia en Luz y Materia Estructuradas (LUMES), Universidad de Salamanca, Salamanca, 37008, Spain
| | - Julio San Roman
- Grupo
de Investigación en Aplicaciones del Láser y Fotónica,
Departamento de Física Aplicada, Universidad de Salamanca, Salamanca, 37008, Spain
- Unidad
de Excelencia en Luz y Materia Estructuradas (LUMES), Universidad de Salamanca, Salamanca, 37008, Spain
| |
Collapse
|
3
|
Biró L, Csehi A. Attosecond Probing of Nuclear Vibrations in the D 2+ and HeH + Molecular Ions. J Phys Chem A 2024; 128:858-867. [PMID: 38277484 DOI: 10.1021/acs.jpca.3c07031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2024]
Abstract
We study the ultrafast photodissociation of small diatomic molecules using attosecond laser pulses of moderate intensity in the (extreme) ultraviolet regime. The simultaneous application of subfemtosecond laser pulses with different photon energies─resonant in the region of the molecular motion─allows one to monitor the vibrational dynamics of simple diatomics, like the D2+ and HeH+ molecular ions. In our real-time wave packet simulations, the nuclear dynamics is initiated either by sudden ionization (D2+) or by explicit pump pulses (HeH+) via distortion of the potential energy of the molecule. The application of time-delayed attosecond pulses leads to the breakup of the molecules, and the information on the underlying bound-state dynamics is imprinted in the kinetic energy release (KER) spectra of the outgoing fragments. We show that the KER-delay spectrograms generated in our ultrafast pump-probe schemes are able to reconstruct the most important features of the molecular motion within a given electronic state, such as the time period or amplitude of oscillations, interference patterns, or the revival and splitting of the nuclear wave packet. The impact of probe pulse duration, which is key to the applicability of the presented mapping scheme, is investigated in detail.
Collapse
Affiliation(s)
- László Biró
- Department of Theoretical Physics, Faculty of Science and Technology, University of Debrecen, H-4002 Debrecen, P.O. Box 400, Hungary
| | - András Csehi
- Department of Theoretical Physics, Faculty of Science and Technology, University of Debrecen, H-4002 Debrecen, P.O. Box 400, Hungary
| |
Collapse
|
4
|
Chen Y, Cheak TZ, Jin TS, Vinitha G, Dimyati K, Harun SW. Domain-wall dark pulse generation with SMF-GIMF-SMF structure as artificial saturable absorber. Sci Rep 2024; 14:2141. [PMID: 38273021 PMCID: PMC10811242 DOI: 10.1038/s41598-024-52640-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 01/22/2024] [Indexed: 01/27/2024] Open
Abstract
We experimentally demonstrated the generation of domain-wall dark pulse in an Erbium-doped fiber laser using the combination of a 10 cm graded index multimode fiber sandwiched by single mode fibers as artificial saturable absorber. The interaction of phase difference in grade index multimode fiber allowed the stable dual-wavelength oscillation in the cavity. The dual-wavelength centered at 1567.2 nm and 1569.4 nm produces the topological defect in temporal domain and achieved a dark pulse formation with repetition rate of 21.5 MHz. The highest average pulse energy is calculated as 769.6 pJ with pulse width of 5 ns. Throughout the operating pump power range, the average pulse energy and output power increase linearly, with R2 of 0.9999 and achieved the laser efficiency of 9.33%. From the measurement in frequency domain, the signal-to-noise ratio is measured as 49 dB. As compared to reported DW dark pulse works, the proposed structure only required a short length of multimode fiber, which allowed the domain-wall dark pulse to achieve higher pulse repetition rate. The venture of domain wall dark pulse is potentially to pave the foundation toward sustainable industrial growth.
Collapse
Affiliation(s)
- Yu Chen
- Chongqing Vocational Institute of Engineering, No. 1, North and South Avenue, Binjiang New City, Jiangjin District, Chongqing, 402260, China
- Photonics Engineering Laboratory, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Tiu Zian Cheak
- Faculty of Engineering and Quantity Surveying, INTI International University, 71800, Nilai, Negeri Sembilan, Malaysia.
- Department of Physics, School of Advanced Sciences, VIT, Chennai, Tamil Nadu, 600127, India.
| | - Tan Sin Jin
- Faculty of Engineering, UOW Malaysia KDU University College, 40150, Shah Alam, Selangor, Malaysia
| | - G Vinitha
- Department of Physics, School of Advanced Sciences, VIT, Chennai, Tamil Nadu, 600127, India
| | - Kaharudin Dimyati
- Photonics Engineering Laboratory, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Sulaiman Wadi Harun
- Photonics Engineering Laboratory, Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| |
Collapse
|
5
|
Appi E, Weissenbilder R, Nagyillés B, Diveki Z, Peschel J, Farkas B, Plach M, Vismarra F, Poulain V, Weber N, Arnold CL, Varjú K, Kahaly S, Eng-Johnsson P, L'Huillier A. Two phase-matching regimes in high-order harmonic generation. OPTICS EXPRESS 2023; 31:31687-31697. [PMID: 37858988 DOI: 10.1364/oe.488298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 07/26/2023] [Indexed: 10/21/2023]
Abstract
High-order harmonic generation (HHG) provides scalable sources of coherent extreme ultraviolet radiation with pulse duration down to the attosecond time scale. Efficient HHG requires the constructive interplay between microscopic and macroscopic effects in the generation volume, which can be achieved over a large range of experimental parameters from the driving field properties to those of the generating medium. Here, we present a systematic study of the harmonic yield as a function of gas pressure and medium length. Two regimes for optimum yield are identified, supporting the predictions of a recently proposed analytical model. Our observations are independent on the focusing geometry and, to a large extent, on the pulse duration and laser intensity, providing a versatile approach to HHG optimization.
Collapse
|
6
|
Reduzzi M, Pini M, Mai L, Cappenberg F, Colaizzi L, Vismarra F, Crego A, Lucchini M, Brahms C, Travers JC, Borrego-Varillas R, Nisoli M. Direct temporal characterization of sub-3-fs deep UV pulses generated by resonant dispersive wave emission. OPTICS EXPRESS 2023; 31:26854-26864. [PMID: 37710535 DOI: 10.1364/oe.494879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 07/19/2023] [Indexed: 09/16/2023]
Abstract
We report on the complete temporal characterization of ultrashort pulses, generated by resonant dispersive wave emission in gas-filled hollow-capillary fibers, with energy in the microjoule range and continuously tunable from the deep-ultraviolet to the ultraviolet. Temporal characterization of such ultrabroad pulses, particularly challenging in this spectral region, was performed using an all-in-vacuum setup for self-diffraction frequency resolved optical gating (SD-FROG). Sub-3-fs pulses were measured, tunable from 250 nm to 350 nm, with a minimum pulse duration of 2.4 ± 0.1 fs.
Collapse
|
7
|
Yehorova D, Kretchmer JS. A multi-fragment real-time extension of projected density matrix embedding theory: Non-equilibrium electron dynamics in extended systems. J Chem Phys 2023; 158:131102. [PMID: 37031109 DOI: 10.1063/5.0146973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
In this work, we derive a multi-fragment real-time extension of the projected density matrix embedding theory (pDMET) designed to treat non-equilibrium electron dynamics in strongly correlated systems. As in the previously developed static pDMET, the real time pDMET partitions the total system into many fragments; the coupling between each fragment and the rest of the system is treated through a compact representation of the environment in terms of a quantum bath. The real-time pDMET involves simultaneously propagating the wavefunctions for each separate fragment–bath embedding system along with an auxiliary mean-field wavefunction of the total system. The equations of motion are derived by (i) projecting the time-dependent Schrödinger equation in the fragment and bath space associated with each separate fragment and by (ii) enforcing the pDMET matching conditions between the global 1-particle reduced density matrix (1-RDM) obtained from the fragment calculations and the mean-field 1-RDM at all points in time. The accuracy of the method is benchmarked through comparisons to time-dependent density-matrix renormalization group and time-dependent Hartree–Fock (TDHF) theory; the methods were applied to a one- and two-dimensional single-impurity Anderson model and multi-impurity Anderson models with ordered and disordered distributions of the impurities. The results demonstrate a large improvement over TDHF and rapid convergence to the exact dynamics with an increase in fragment size. Our results demonstrate that the real-time pDMET is a promising and flexible method that balances accuracy and efficiency to simulate the non-equilibrium electron dynamics in heterogeneous systems of large size.
Collapse
Affiliation(s)
- Dariia Yehorova
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Joshua S. Kretchmer
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| |
Collapse
|
8
|
Venkatesh M, Kim VV, Boltaev GS, Konda SR, Svedlindh P, Li W, Ganeev RA. High-Order Harmonics Generation in MoS2 Transition Metal Dichalcogenides: Effect of Nickel and Carbon Nanotube Dopants. Int J Mol Sci 2023; 24:ijms24076540. [PMID: 37047513 PMCID: PMC10094757 DOI: 10.3390/ijms24076540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/21/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023] Open
Abstract
The transition metal dichalcogenides have instigated a lot of interest as harmonic generators due to their exceptional nonlinear optical properties. Here, the molybdenum disulfide (MoS2) molecular structures with dopants being in a plasma state are used to demonstrate the generation of intense high-order harmonics. The MoS2 nanoflakes and nickel-doped MoS2 nanoflakes produced stronger harmonics with higher cut-offs compared with Mo bulk and MoS2 bulk. Conversely, the MoS2 with nickel nanoparticles and carbon nanotubes (MoS2-NiCNT) produced weaker coherent XUV emissions than other materials, which is attributed to the influence of phase mismatch. The influence of heating and driving pulse intensities on the harmonic yield and cut-off energies are investigated in MoS2 molecular structures. The enhanced coherent extreme ultraviolet emission at ~32 nm (38 eV) due to the 4p-4d resonant transitions is obtained from all aforementioned molecular structures, except for MoS2-NiCNT.
Collapse
Affiliation(s)
- Mottamchetty Venkatesh
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Department of Materials Science and Engineering, Uppsala University, P.O. Box 35, SE-75103 Uppsala, Sweden
- Correspondence: (M.V.); (R.A.G.)
| | - Vyacheslav V. Kim
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Laboratory of Nonlinear Optics, University of Latvia, Jelgavas 3, LV-1004 Riga, Latvia
- Institute of Fundamental and Applied Research, TIIAME National Research University, Kori Niyoziy 39, Tashkent 100000, Uzbekistan
| | - Ganjaboy S. Boltaev
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Institute of Fundamental and Applied Research, TIIAME National Research University, Kori Niyoziy 39, Tashkent 100000, Uzbekistan
- Faculty of Physics and Matematics, Chirchik State Pedagogical University, 104 Amir Temur, Chirchik 111700, Uzbekistan
| | - Srinivasa Rao Konda
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Peter Svedlindh
- Department of Materials Science and Engineering, Uppsala University, P.O. Box 35, SE-75103 Uppsala, Sweden
| | - Wei Li
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Rashid A. Ganeev
- GPL Photonics Laboratory, State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
- Laboratory of Nonlinear Optics, University of Latvia, Jelgavas 3, LV-1004 Riga, Latvia
- Institute of Fundamental and Applied Research, TIIAME National Research University, Kori Niyoziy 39, Tashkent 100000, Uzbekistan
- Faculty of Physics and Matematics, Chirchik State Pedagogical University, 104 Amir Temur, Chirchik 111700, Uzbekistan
- Department of Physics, Voronezh State University, 394006 Voronezh, Russia
- Correspondence: (M.V.); (R.A.G.)
| |
Collapse
|
9
|
Lucchini M, Mignolet B, Murari M, Gonçalves CEM, Lucarelli GD, Frassetto F, Poletto L, Remacle F, Nisoli M. Few-Femtosecond C 2H 4+ Internal Relaxation Dynamics Accessed by Selective Excitation. J Phys Chem Lett 2022; 13:11169-11175. [PMID: 36445180 PMCID: PMC9937561 DOI: 10.1021/acs.jpclett.2c02763] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/28/2022] [Indexed: 06/16/2023]
Abstract
Dissociation of the ethylene cation is a prototypical multistep pathway in which the exact mechanisms leading to internal energy conversions are not fully known. For example, it is still unclear how the energy is exactly redistributed among the internal modes and which step is rate-determining. Here we use few-femtosecond extreme-ultraviolet pulses of tunable energy to excite a different superposition of the four lowest states of C2H4+ and probe the subsequent fast relaxation with a short infrared pulse. Our results demonstrate that the infrared pulse photoexcites the cationic ground state (GS) to higher excited states, producing a hot GS upon relaxation, which enhances the fragmentation yield. As the photoexcitation probability of the GS strongly depends on the molecular geometry, the probing by the IR pulse provides information about the ultrafast excited-state dynamics and the type of conical intersection (planar or twisted) involved in the first 20 fs of the nonradiative relaxation.
Collapse
Affiliation(s)
- Matteo Lucchini
- Department
of Physics, Politecnico di Milano, 20133 Milano, Italy
- Institute
for Photonics and Nanotechnologies, IFN-CNR, 20133 Milano, Italy
| | - Benoit Mignolet
- Theoretical
Physical Chemistry, UR MOLSYS, University
of Liège, B4000 Liège, Belgium
| | - Mario Murari
- Department
of Physics, Politecnico di Milano, 20133 Milano, Italy
- Institute
for Photonics and Nanotechnologies, IFN-CNR, 20133 Milano, Italy
| | - Cayo E. M. Gonçalves
- Theoretical
Physical Chemistry, UR MOLSYS, University
of Liège, B4000 Liège, Belgium
| | | | - Fabio Frassetto
- Institute
for Photonics and Nanotechnologies, IFN-CNR, 35131 Padova, Italy
| | - Luca Poletto
- Institute
for Photonics and Nanotechnologies, IFN-CNR, 35131 Padova, Italy
| | - Françoise Remacle
- Theoretical
Physical Chemistry, UR MOLSYS, University
of Liège, B4000 Liège, Belgium
| | - Mauro Nisoli
- Department
of Physics, Politecnico di Milano, 20133 Milano, Italy
- Institute
for Photonics and Nanotechnologies, IFN-CNR, 20133 Milano, Italy
| |
Collapse
|
10
|
Controlling Floquet states on ultrashort time scales. Nat Commun 2022; 13:7103. [DOI: 10.1038/s41467-022-34973-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 11/14/2022] [Indexed: 11/21/2022] Open
Abstract
AbstractThe advent of ultrafast laser science offers the unique opportunity to combine Floquet engineering with extreme time resolution, further pushing the optical control of matter into the petahertz domain. However, what is the shortest driving pulse for which Floquet states can be realised remains an unsolved matter, thus limiting the application of Floquet theory to pulses composed by many optical cycles. Here we ionized Ne atoms with few-femtosecond pulses of selected time duration and show that a Floquet state can be observed already with a driving field that lasts for only 10 cycles. For shorter pulses, down to 2 cycles, the finite lifetime of the driven state can still be explained using an analytical model based on Floquet theory. By demonstrating that the amplitude and number of Floquet-like sidebands in the photoelectron spectrum can be controlled not only with the driving laser pulse intensity and frequency, but also by its duration, our results add a new lever to the toolbox of Floquet engineering.
Collapse
|