1
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Driver T, Mountney M, Wang J, Ortmann L, Al-Haddad A, Berrah N, Bostedt C, Champenois EG, DiMauro LF, Duris J, Garratt D, Glownia JM, Guo Z, Haxton D, Isele E, Ivanov I, Ji J, Kamalov A, Li S, Lin MF, Marangos JP, Obaid R, O'Neal JT, Rosenberger P, Shivaram NH, Wang AL, Walter P, Wolf TJA, Wörner HJ, Zhang Z, Bucksbaum PH, Kling MF, Landsman AS, Lucchese RR, Emmanouilidou A, Marinelli A, Cryan JP. Attosecond delays in X-ray molecular ionization. Nature 2024; 632:762-767. [PMID: 39169246 DOI: 10.1038/s41586-024-07771-9] [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: 12/30/2023] [Accepted: 07/01/2024] [Indexed: 08/23/2024]
Abstract
The photoelectric effect is not truly instantaneous but exhibits attosecond delays that can reveal complex molecular dynamics1-7. Sub-femtosecond-duration light pulses provide the requisite tools to resolve the dynamics of photoionization8-12. Accordingly, the past decade has produced a large volume of work on photoionization delays following single-photon absorption of an extreme ultraviolet photon. However, the measurement of time-resolved core-level photoionization remained out of reach. The required X-ray photon energies needed for core-level photoionization were not available with attosecond tabletop sources. Here we report measurements of the X-ray photoemission delay of core-level electrons, with unexpectedly large delays, ranging up to 700 as in NO near the oxygen K-shell threshold. These measurements exploit attosecond soft X-ray pulses from a free-electron laser to scan across the entire region near the K-shell threshold. Furthermore, we find that the delay spectrum is richly modulated, suggesting several contributions, including transient trapping of the photoelectron owing to shape resonances, collisions with the Auger-Meitner electron that is emitted in the rapid non-radiative relaxation of the molecule and multi-electron scattering effects. The results demonstrate how X-ray attosecond experiments, supported by comprehensive theoretical modelling, can unravel the complex correlated dynamics of core-level photoionization.
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Affiliation(s)
- Taran Driver
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
| | - Miles Mountney
- Department of Physics and Astronomy, University College London, London, UK
| | - Jun Wang
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Lisa Ortmann
- Department of Physics, The Ohio State University, Columbus, OH, USA
| | | | - Nora Berrah
- Department of Physics, University of Connecticut, Storrs, CT, USA
| | - Christoph Bostedt
- Paul Scherrer Institute, Villigen, Switzerland
- LUXS Laboratory for Ultrafast X-ray Sciences, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Elio G Champenois
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Louis F DiMauro
- Department of Physics, The Ohio State University, Columbus, OH, USA
| | - Joseph Duris
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Douglas Garratt
- The Blackett Laboratory, Imperial College London, London, UK
| | - James M Glownia
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Zhaoheng Guo
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | | | - Erik Isele
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Igor Ivanov
- Center for Relativistic Laser Science, Institute for Basic Science, Gwangju, Korea
| | - Jiabao Ji
- Laboratorium für Physikalische Chemie, ETH Zurich, Zurich, Switzerland
| | - Andrei Kamalov
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Siqi Li
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Ming-Fu Lin
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Jon P Marangos
- The Blackett Laboratory, Imperial College London, London, UK
| | - Razib Obaid
- Department of Physics, University of Connecticut, Storrs, CT, USA
| | - Jordan T O'Neal
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Philipp Rosenberger
- Physics Department, Ludwig-Maximilians-Universität, Munich, Germany
- Max Planck Institute of Quantum Optics, Garching, Germany
| | - Niranjan H Shivaram
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, IN, USA
| | - Anna L Wang
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Peter Walter
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Thomas J A Wolf
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Hans Jakob Wörner
- Laboratorium für Physikalische Chemie, ETH Zurich, Zurich, Switzerland
| | - Zhen Zhang
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Philip H Bucksbaum
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Matthias F Kling
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Physics Department, Ludwig-Maximilians-Universität, Munich, Germany
- Max Planck Institute of Quantum Optics, Garching, Germany
| | | | - Robert R Lucchese
- Purdue Quantum Science and Engineering Institute, Purdue University, West Lafayette, IN, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | - Agostino Marinelli
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
| | - James P Cryan
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
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2
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Ortmann L, Landsman A. Understanding attosecond streaking. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:086401. [PMID: 38996411 DOI: 10.1088/1361-6633/ad6278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 07/12/2024] [Indexed: 07/14/2024]
Abstract
This tutorial provides an overview on the theory of attosecond streaking, a pump-probe scheme to extract timing information of ionization processes that has been widely used in the past decade. Emphasis is put on the origin of the Coulomb-laser-coupling (CLC) term, which is crucial in the interpretation of streaking delays. Having gained a proper understanding of how the CLC terms in various publications relate to each other, we will be able to analyze in which regime the streaking delay can be split into a measurement-induced CLC term and a 'pure' ionization delay and under which conditions this splitting may break down. Thus we address the long-standing question of the validity of the widely applied interpretation of the streaking delay as a sum of the CLC term and a 'pure' ionization delay.
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Affiliation(s)
- Lisa Ortmann
- Department of Physics, The Ohio State University, Columbus, OH 43210, United States of America
| | - Alexandra Landsman
- Department of Physics, The Ohio State University, Columbus, OH 43210, United States of America
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3
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Orimo Y, Sato T, Ishikawa KL. Use of Erfgau Potential for Simulations of Multielectron Dynamics in Intense Laser Pulses. J Phys Chem A 2023. [PMID: 38036489 DOI: 10.1021/acs.jpca.3c06530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2023]
Abstract
We propose the use of the erfgau potential as a smooth alternative to the pure Coulomb potential between nuclei and electrons in simulating the dynamics of electrons within atoms and molecules driven by high-intensity laser pulses. Even without the sophistication of pseudopotentials, by utilizing a well-designed simple approximate potential, it is possible to make the simulations computationally less demanding while keeping accuracy. By employing the erfgau potential designed for the stationary state of hydrogen-like atoms, we demonstrate that it is possible to simulate not only the high harmonic generation from a hydrogen atom but also that of multielectron systems, including molecules.
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Affiliation(s)
- Yuki Orimo
- Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takeshi Sato
- Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Research Institute for Photon Science and Laser Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Photon Science Center, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Kenichi L Ishikawa
- Department of Nuclear Engineering and Management, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
- Research Institute for Photon Science and Laser Technology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Photon Science Center, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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4
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Borràs VJ, González-Vázquez J, Argenti L, Martín F. Attosecond photoionization delays in the vicinity of molecular Feshbach resonances. SCIENCE ADVANCES 2023; 9:eade3855. [PMID: 37043566 PMCID: PMC10096576 DOI: 10.1126/sciadv.ade3855] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 03/13/2023] [Indexed: 06/19/2023]
Abstract
Temporal delays extracted from photoionization phases are currently determined with attosecond resolution by using interferometric methods. Such methods require special care when photoionization occurs near Feshbach resonances due to the interference between direct ionization and autoionization. Although theory can accurately handle these interferences in atoms, in molecules, it has to face an additional, so far insurmountable problem: Autoionization is slow, and nuclei move substantially while it happens, i.e., electronic and nuclear motions are coupled. Here, we present a theoretical framework to account for this effect and apply it to evaluate time-resolved and vibrationally resolved photoelectron spectra and photoionization phases of N2 irradiated by a combination of an extreme ultraviolet (XUV) attosecond pulse train and an infrared pulse. We show that Feshbach resonances lead to unusual non-Franck-Condon vibrational progressions and to ionization phases that strongly vary with photoelectron energy irrespective of the vibrational state of the remaining molecular cation.
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Affiliation(s)
- Vicent J. Borràs
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Jesús González-Vázquez
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Luca Argenti
- Department of Physics and CREOL, University of Central Florida, Orlando, FL 32186, USA
| | - Fernando Martín
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nano), Cantoblanco, 28049 Madrid, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
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5
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Shake-Off Process in Non-Sequential Single-Photon Double Ionization of Closed-Shell Atomic Targets. ATOMS 2022. [DOI: 10.3390/atoms10030089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Amusia and Kheifets in 1984 introduced a Green’s function formalism to describe the effect of many-electron correlation on the ionization spectra of atoms. Here, we exploit this formalism to model the shake-off (SO) process, leading to the non-sequential single-photon two-electron ionization (double photoionization—DPI) of closed-shell atomic targets. We separate the SO process from another knock-out (KO) mechanism of DPI and show the SO prevalence away from the DPI threshold. We use this kinematic regime to validate our model by making a comparison with more elaborate techniques, such as convergent and time-dependent close coupling. We also use our model to evaluate the attosecond time delay associated with the SO process. Typically, the SO is very fast, taking only a few attoseconds to complete. However, it can take much longer in the DPI of strongly correlated systems, such as the H− ion as well as the subvalent shells of the Ar and Xe atoms and Cl− ion.
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6
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Borrego-Varillas R, Lucchini M, Nisoli M. Attosecond spectroscopy for the investigation of ultrafast dynamics in atomic, molecular and solid-state physics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:066401. [PMID: 35294930 DOI: 10.1088/1361-6633/ac5e7f] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
Since the first demonstration of the generation of attosecond pulses (1 as = 10-18s) in the extreme-ultraviolet spectral region, several measurement techniques have been introduced, at the beginning for the temporal characterization of the pulses, and immediately after for the investigation of electronic and nuclear ultrafast dynamics in atoms, molecules and solids with unprecedented temporal resolution. The attosecond spectroscopic tools established in the last two decades, together with the development of sophisticated theoretical methods for the interpretation of the experimental outcomes, allowed to unravel and investigate physical processes never observed before, such as the delay in photoemission from atoms and solids, the motion of electrons in molecules after prompt ionization which precede any notable nuclear motion, the temporal evolution of the tunneling process in dielectrics, and many others. This review focused on applications of attosecond techniques to the investigation of ultrafast processes in atoms, molecules and solids. Thanks to the introduction and ongoing developments of new spectroscopic techniques, the attosecond science is rapidly moving towards the investigation, understanding and control of coupled electron-nuclear dynamics in increasingly complex systems, with ever more accurate and complete investigation techniques. Here we will review the most common techniques presenting the latest results in atoms, molecules and solids.
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Affiliation(s)
- Rocío Borrego-Varillas
- Institute for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Matteo Lucchini
- Institute for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Mauro Nisoli
- Institute for Photonics and Nanotechnologies (IFN), Consiglio Nazionale delle Ricerche (CNR), Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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7
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Time Delay in Electron Collision with a Spherical Target as a Function of the Scattering Angle. ATOMS 2021. [DOI: 10.3390/atoms9040105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We have studied the angular time delay in slow-electron elastic scattering by spherical targets as well as the average time delay of electrons in this process. It is demonstrated how the angular time delay is connected to the Eisenbud–Wigner–Smith (EWS) time delay. The specific features of both angular and energy dependencies of these time delays are discussed in detail. The potentialities of the derived general formulas are illustrated by the numerical calculations of the time delays of slow electrons in the potential fields of both absolutely hard-sphere and delta-shell potential well of the same radius. The conducted studies shed more light on the specific features of these time delays.
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8
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Deshmukh PC, Banerjee S. Time delay in atomic and molecular collisions and photoionisation/photodetachment. INT REV PHYS CHEM 2020. [DOI: 10.1080/0144235x.2021.1838805] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- P. C. Deshmukh
- Department of Physics and CAMOST, Indian Institute of Technology Tirupati, Tirupati, India
- Department of Physics, Dayananda Sagar University, Bengaluru, India
| | - Sourav Banerjee
- Department of Physics, Indian Institute of Technology Madras, Chennai, India
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9
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Saalmann U, Rost JM. Proper Time Delays Measured by Optical Streaking. PHYSICAL REVIEW LETTERS 2020; 125:113202. [PMID: 32975971 DOI: 10.1103/physrevlett.125.113202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
In attosecond science it is assumed that Wigner-Smith time delays, known from scattering theory, are determined by measuring streaking shifts. Despite their wide use from atoms to solids this has never been proven. Analyzing the underlying process-energy absorption from the streaking light-we derive this relation. It reveals that only under specific conditions streaking shifts measure Wigner-Smith time delays. For the most relevant case, interactions containing long-range Coulomb tails, we show that finite streaking shifts, including relative shifts from two different orbitals, are misleading. We devise a new time-delay definition and describe a measurement technique that avoids the record of a complete streaking scan, as suggested by the relation between time delays and streaking shifts.
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Affiliation(s)
- Ulf Saalmann
- Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, 01187 Dresden, Germany
| | - Jan M Rost
- Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Straße 38, 01187 Dresden, Germany
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10
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Wigner Time-Delay and Distribution for Polarization Interaction in Strongly Coupled Semiclassical Plasmas. ENTROPY 2020; 22:e22090910. [PMID: 33286679 PMCID: PMC7597152 DOI: 10.3390/e22090910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 08/17/2020] [Accepted: 08/17/2020] [Indexed: 11/23/2022]
Abstract
The quantum effect on the Wigner time-delay and distribution for the polarization scattering in a semiclassical dense plasma is explored. The partial wave analysis is applied for a partially ionized dense plasma to derive the phase shift for the polarization interaction. The Wigner time-delay and the Wigner distribution are derived for the electron–atom polarization interaction including the effects of quantum-mechanical characteristic and plasma screening. In this work, we show that the Wigner time-delay and the Wigner distribution for the polarization interaction can be suppressed by the quantum effect. The Wigner time-delay and the Wigner distribution are also significantly suppressed by the increase of plasma shielding. The variation of the Wigner time-delay and the Wigner distribution function due to quantum screening is discussed.
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11
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Liang J, Zhou Y, Tan J, He M, Ke Q, Zhao Y, Li M, Jiang W, Lu P. Low-energy photoelectron interference structure in attosecond streaking. OPTICS EXPRESS 2019; 27:37736-37752. [PMID: 31878550 DOI: 10.1364/oe.27.037736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
By numerically solving the time-dependent Schrödinger equation, we theoretically investigate the dynamics of the low-energy photoelectrons ionized by a single attosecond pulse in the presence of an infrared laser field. The obtained photoelectron momentum distributions exhibit complicated interference structures. With the semiclassical model, the originations for the different types of the interference structures are unambiguously identified. Moreover, by changing the time delay between the attosecond pulse and the infrared laser field, these interferences could be selectively enhanced or suppressed. This enables us to extract information about the ionization dynamics encoded in the interference structures. As an example, we show that the phase of the electron wave-packets ionized by the linearly and circularly polarized attosecond pulses can be extracted from the interference structures of the direct and the near-forward rescattering electrons.
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12
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Hartmann M, Stooß V, Birk P, Borisova G, Ott C, Pfeifer T. Attosecond precision in delay measurements using transient absorption spectroscopy. OPTICS LETTERS 2019; 44:4749-4752. [PMID: 31568433 DOI: 10.1364/ol.44.004749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Abstract
Accessing attosecond (as) dynamics directly in the time domain has been achieved by several pioneering experiments over the course of the last decade. Extreme ultraviolet (XUV) group delays and, later, ionization time delays on the order of a few attoseconds have been extracted by photoemission or high-harmonic spectroscopy. Here, we present and benchmark an approach based on attosecond transient absorption spectroscopy to quantify deliberately induced delays by employing resonant photoexcitation of three XUV transitions with a precision of less than 5 as. While here we quantify the sensitivity to these delays via a chirp on the attosecond pulse by using thin-foil metallic filters, the method enables future studies of attosecond delays probed through resonant excitations.
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13
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Schmid G, Schnorr K, Augustin S, Meister S, Lindenblatt H, Trost F, Liu Y, Stojanovic N, Al-Shemmary A, Golz T, Treusch R, Gensch M, Kübel M, Foucar L, Rudenko A, Ullrich J, Schröter CD, Pfeifer T, Moshammer R. Terahertz-Field-Induced Time Shifts in Atomic Photoemission. PHYSICAL REVIEW LETTERS 2019; 122:073001. [PMID: 30848607 DOI: 10.1103/physrevlett.122.073001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Indexed: 06/09/2023]
Abstract
Time delays for atomic photoemission obtained in streaking or reconstruction of attosecond bursts by interference of two-photon transitions experiments originate from a combination of the quantum mechanical Wigner time and the Coulomb-laser coupling. While the former was investigated intensively theoretically as well as experimentally, the latter attracted less interest in experiments and has mostly been subject to calculations. Here, we present a measurement of the Coulomb-laser coupling-induced time shifts in photoionization of neon at 59.4 eV using a terahertz (THz) streaking field (λ=152 μm). Employing a reaction microscope at the THz beamline of the free-electron laser in Hamburg (FLASH), we have measured relative time shifts of up to 70 fs between the emission of 2p photoelectrons (∼38 eV) and low-energetic (<1 eV) photoelectrons. A comparison with theoretical predictions on Coulomb-laser coupling reveals reasonably good agreement.
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Affiliation(s)
- Georg Schmid
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Kirsten Schnorr
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Sven Augustin
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Severin Meister
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Hannes Lindenblatt
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Florian Trost
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Yifan Liu
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Nikola Stojanovic
- Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, D-22607 Hamburg, Germany
| | - Alaa Al-Shemmary
- Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, D-22607 Hamburg, Germany
| | - Torsten Golz
- Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, D-22607 Hamburg, Germany
| | - Rolf Treusch
- Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, D-22607 Hamburg, Germany
| | - Michael Gensch
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, D-01328 Dresden, Germany
| | - Matthias Kübel
- Department of Physics, Ludwig-Maximilians-Universität München, D-85748 Garching, Germany
- Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Straße 1, D-85748 Garching, Germany
| | - Lutz Foucar
- Max-Planck-Institut für medizinsche Forschung, Jahnstraße 29, D-69120 Heidelberg, Germany
| | - Artem Rudenko
- Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506, USA
| | - Joachim Ullrich
- Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, D-38116 Braunschweig, Germany
| | | | - Thomas Pfeifer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - Robert Moshammer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
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14
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Song X, Shi G, Zhang G, Xu J, Lin C, Chen J, Yang W. Attosecond Time Delay of Retrapped Resonant Ionization. PHYSICAL REVIEW LETTERS 2018; 121:103201. [PMID: 30240251 DOI: 10.1103/physrevlett.121.103201] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 07/10/2018] [Indexed: 06/08/2023]
Abstract
A recent ultrafast pump-probe technique has allowed measurement of time delays during photoemission in a variety of systems ranging from atoms and molecules to solids with unprecedented temporal resolution. However, identifying the underlying physics is still a challenge especially in complicated multichannel above-threshold ionization (ATI) experiments. Here we demonstrate that the time delays of different ionization pathways in ATI can be clearly resolved and extracted with a semiclassical statistical method. The remarkable phase shift of near threshold photoelectrons can be attributed to a temporary retrapping of a photoelectron by the atomic potential in a quasibound state after emerging in the continuum state. This continuum-bound-continuum scattering manifests as a new resonant effect in strong-field photoemission. Our results unify the seemingly opposing quantum Eisenbud-Wigner-Smith time delay and classical Coulomb-induced time delay by highlighting the same physical picture, which holds promise for an intuitive interpretation of time-resolved fundamental electronic processes in strong-field experiments and epistemological reexamination of the quantum-classical correspondence.
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Affiliation(s)
- Xiaohong Song
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
| | - Guangluo Shi
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
| | - Guojun Zhang
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
| | - Jingwen Xu
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
| | - Cheng Lin
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
| | - Jing Chen
- Key Laboratory of High Energy Density Physics Simulation, Center for Applied Physics and Technology, Peking University, Beijing 100084, China
- Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088, China
- Collaborative Innovation Center of Inertial Fusion Sciences and Applications, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Weifeng Yang
- Department of Physics, College of Science, Shantou University, Shantou, Guangdong 515063, China
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15
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Anisotropic photoemission time delays close to a Fano resonance. Nat Commun 2018; 9:955. [PMID: 29511164 PMCID: PMC5840338 DOI: 10.1038/s41467-018-03009-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 01/12/2018] [Indexed: 11/24/2022] Open
Abstract
Electron correlation and multielectron effects are fundamental interactions that govern many physical and chemical processes in atomic, molecular and solid state systems. The process of autoionization, induced by resonant excitation of electrons into discrete states present in the spectral continuum of atomic and molecular targets, is mediated by electron correlation. Here we investigate the attosecond photoemission dynamics in argon in the 20–40 eV spectral range, in the vicinity of the 3s−1np autoionizing resonances. We present measurements of the differential photoionization cross section and extract energy and angle-dependent atomic time delays with an attosecond interferometric method. With the support of a theoretical model, we are able to attribute a large part of the measured time delay anisotropy to the presence of autoionizing resonances, which not only distort the phase of the emitted photoelectron wave packet but also introduce an angular dependence. Ionization time delays are of interest in understanding the photoionization mechanism in atoms and molecules in ultra-short time scales. Here the authors investigate the angular dependence of photoionization time delays in the presence of an autoionizing resonance in argon atom using RABBITT technique.
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16
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Ultrafast quantum control of ionization dynamics in krypton. Nat Commun 2018; 9:719. [PMID: 29459621 PMCID: PMC5818503 DOI: 10.1038/s41467-018-03122-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 01/19/2018] [Indexed: 11/08/2022] Open
Abstract
Ultrafast spectroscopy with attosecond resolution has enabled the real time observation of ultrafast electron dynamics in atoms, molecules and solids. These experiments employ attosecond pulses or pulse trains and explore dynamical processes in a pump–probe scheme that is selectively sensitive to electronic state of matter via photoelectron or XUV absorption spectroscopy or that includes changes of the ionic state detected via photo-ion mass spectrometry. Here, we demonstrate how the implementation of combined photo-ion and absorption spectroscopy with attosecond resolution enables tracking the complex multidimensional excitation and decay cascade of an Auger auto-ionization process of a few femtoseconds in highly excited krypton. In tandem with theory, our study reveals the role of intermediate electronic states in the formation of multiply charged ions. Amplitude tuning of a dressing laser field addresses different groups of decay channels and allows exerting temporal and quantitative control over the ionization dynamics in rare gas atoms. Photoionization of atoms and molecules is a complex process and requires sensitive probes to explore the ultrafast dynamics. Here the authors combine transient absorption and photo-ion spectroscopy methods to explore and control the attosecond pulse initiated excitation, ionization and Auger decay in Kr atoms.
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17
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Chacón A, Ruiz C. Attosecond delay in the molecular photoionization of asymmetric molecules. OPTICS EXPRESS 2018; 26:4548-4562. [PMID: 29475304 DOI: 10.1364/oe.26.004548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/15/2017] [Indexed: 06/08/2023]
Abstract
We report theoretical calculations of the delay in photoemission from CO with particular emphasis on the role of the ultrafast electronic bound dynamics. We study the delays in photoionization in the HOMO and HOMO-1 orbitals of the CO molecule by looking into the stereo Wigner time delay technique. That compares the delay in photoemission from electrons emitted to the left and right to extract structural and dynamical information of the ionization process. For this we apply two techniques: The attosecond streak camera and the time of flight technique. Although they should provide the same results we have found large discrepancies of up to 36 in the case of HOMO, while for the HOMO-1 we obtain the same results with the two techniques. We have found that the large time delays observed in the HOMO orbital with the streaking technique are a consequence of the resonant transition triggered by the streaking field. This resonant transition produces a bound electron wavepacket that modifies the measurements of delay in photoionization. As a result of this observation, our technique allows us to reconstruct the bound wavepacket dynamics induced by the streaking field. By measuring the expected value of the electron momentum along the polarization direction after the streaking field has finished, we can recover the relative phase between the complex amplitudes of the HOMO and LUMO orbitals. These theoretical calculations pave the way for the measurement of ultrafast bound-bound electron transitionsand its crucial role for the delay in photoemission observation.
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18
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Gallmann L, Jordan I, Wörner HJ, Castiglioni L, Hengsberger M, Osterwalder J, Arrell CA, Chergui M, Liberatore E, Rothlisberger U, Keller U. Photoemission and photoionization time delays and rates. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:061502. [PMID: 29308414 PMCID: PMC5732014 DOI: 10.1063/1.4997175] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 11/02/2017] [Indexed: 05/20/2023]
Abstract
Ionization and, in particular, ionization through the interaction with light play an important role in fundamental processes in physics, chemistry, and biology. In recent years, we have seen tremendous advances in our ability to measure the dynamics of photo-induced ionization in various systems in the gas, liquid, or solid phase. In this review, we will define the parameters used for quantifying these dynamics. We give a brief overview of some of the most important ionization processes and how to resolve the associated time delays and rates. With regard to time delays, we ask the question: how long does it take to remove an electron from an atom, molecule, or solid? With regard to rates, we ask the question: how many electrons are emitted in a given unit of time? We present state-of-the-art results on ionization and photoemission time delays and rates. Our review starts with the simplest physical systems: the attosecond dynamics of single-photon and tunnel ionization of atoms in the gas phase. We then extend the discussion to molecular gases and ionization of liquid targets. Finally, we present the measurements of ionization delays in femto- and attosecond photoemission from the solid-vacuum interface.
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Affiliation(s)
- L Gallmann
- Department of Physics, Institute of Quantum Electronics, ETH Zurich, 8093 Zurich, Switzerland
| | - I Jordan
- Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - H J Wörner
- Laboratorium für Physikalische Chemie, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - L Castiglioni
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - M Hengsberger
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - J Osterwalder
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - C A Arrell
- Laboratoire de Spectroscopie Ultrarapide (LSU), and Lausanne Centre for Ultrafast Science (LACUS), ISIC-FSB, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - M Chergui
- Laboratoire de Spectroscopie Ultrarapide (LSU), and Lausanne Centre for Ultrafast Science (LACUS), ISIC-FSB, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - E Liberatore
- Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - U Rothlisberger
- Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - U Keller
- Department of Physics, Institute of Quantum Electronics, ETH Zurich, 8093 Zurich, Switzerland
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19
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Fanciulli M, Volfová H, Muff S, Braun J, Ebert H, Minár J, Heinzmann U, Dil JH. Spin Polarization and Attosecond Time Delay in Photoemission from Spin Degenerate States of Solids. PHYSICAL REVIEW LETTERS 2017; 118:067402. [PMID: 28234536 DOI: 10.1103/physrevlett.118.067402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Indexed: 06/06/2023]
Abstract
After photon absorption, electrons from a dispersive band of a solid require a finite time in the photoemission process before being photoemitted as free particles, in line with recent attosecond-resolved photoemission experiments. According to the Eisenbud-Wigner-Smith model, the time delay is due to a phase shift of different transitions that occur in the process. Such a phase shift is also at the origin of the angular dependent spin polarization of the photoelectron beam, observable in spin degenerate systems without angular momentum transfer by the incident photon. We propose a semiquantitative model which permits us to relate spin and time scales in photoemission from condensed matter targets and to better understand spin- and angle-resolved photoemission spectroscopy (SARPES) experiments on spin degenerate systems. We also present the first experimental determination by SARPES of this time delay in a dispersive band, which is found to be greater than 26 as for electrons emitted from the sp-bulk band of the model system Cu(111).
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Affiliation(s)
- Mauro Fanciulli
- Institut de Physique, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Henrieta Volfová
- Department of Chemistry, Ludwig Maximillian University, D-81377 Munich, Germany
| | - Stefan Muff
- Institut de Physique, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Jürgen Braun
- Department of Chemistry, Ludwig Maximillian University, D-81377 Munich, Germany
| | - Hubert Ebert
- Department of Chemistry, Ludwig Maximillian University, D-81377 Munich, Germany
| | - Jan Minár
- Department of Chemistry, Ludwig Maximillian University, D-81377 Munich, Germany
- New Technologies-Research Center, University of West Bohemia, CZ-30614 Pilsen, Czech Republic
| | - Ulrich Heinzmann
- Faculty of Physics, University of Bielefeld, D-33501 Bielefeld, Germany
| | - J Hugo Dil
- Institut de Physique, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Swiss Light Source, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
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20
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Kheifets AS, Bray AW, Bray I. Attosecond Time Delay in Photoemission and Electron Scattering near Threshold. PHYSICAL REVIEW LETTERS 2016; 117:143202. [PMID: 27740835 DOI: 10.1103/physrevlett.117.143202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Indexed: 06/06/2023]
Abstract
We study the time delay in the primary photoemission channel near the opening of an additional channel and compare it with the Wigner time delay in elastic scattering of the photoelectron near the corresponding inelastic threshold. The photoemission time delay near threshold is significantly enhanced, to a measurable 40 as, in comparison to the corresponding elastic scattering delay. The enhancement is due to the different lowest order of interelectron interaction coupling the primary and additional photoemission channels. We illustrate these findings by considering photodetachment from the H^{-} negative ion, and compare it with electron scattering on the hydrogen atom near the first excitation threshold. Other threshold processes of atomic photoionization and molecular photofragmentation, where photoemission time delay is enhanced, are identified. This opens the possibility of studying threshold behavior utilizing attosecond chronoscopy.
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Affiliation(s)
- Anatoli S Kheifets
- Research School of Physics and Engineering, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Alexander W Bray
- Research School of Physics and Engineering, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Igor Bray
- Curtin Institute for Computation and Department of Physics, Astronomy and Medical Radiation Science, Curtin University, Perth, Western Australia 6845, Australia
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21
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Guggenmos A, Akil A, Ossiander M, Schäffer M, Azzeer AM, Boehm G, Amann MC, Kienberger R, Schultze M, Kleineberg U. Attosecond photoelectron streaking with enhanced energy resolution for small-bandgap materials. OPTICS LETTERS 2016; 41:3714-3717. [PMID: 27519070 DOI: 10.1364/ol.41.003714] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Attosecond photoelectron streaking spectroscopy allows time-resolved electron dynamics with a temporal resolution approaching the atomic unit of time. Studies have been performed in numerous systems, including atoms, molecules, and surfaces, and the quest for ever higher temporal resolution called for ever wider spectral extent of the attosecond pulses. For typical experiments relying on attosecond pulses with a duration of 200 as, the time-bandwidth limitation for a Gaussian pulse implies a minimal spectral bandwidth larger than 9 eV translating to a corresponding spread of the detected photoelectron kinetic energies. Here, by utilizing a specially tailored narrowband reflective XUV multilayer mirror, we explore experimentally the minimal spectral width compatible with attosecond time-resolved photoelectron spectroscopy while obtaining the highest possible spectral resolution. The validity of the concept is proven by recording attosecond electron streaking traces from the direct semiconductor gallium arsenide (GaAs), with a nominal bandgap of 1.42 eV at room temperature, proving the potential of the approach for tracking charge dynamics also in these technologically highly relevant materials that previously have been inaccessible to attosecond science.
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22
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Lucchini M, Castiglioni L, Kasmi L, Kliuiev P, Ludwig A, Greif M, Osterwalder J, Hengsberger M, Gallmann L, Keller U. Light-Matter Interaction at Surfaces in the Spatiotemporal Limit of Macroscopic Models. PHYSICAL REVIEW LETTERS 2015; 115:137401. [PMID: 26451581 DOI: 10.1103/physrevlett.115.137401] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Indexed: 06/05/2023]
Abstract
What is the spatiotemporal limit of a macroscopic model that describes the optoelectronic interaction at the interface between different media? This fundamental question has become relevant for time-dependent photoemission from solid surfaces using probes that resolve attosecond electron dynamics on an atomic length scale. We address this fundamental question by investigating how ultrafast electron screening affects the infrared field distribution for a noble metal such as Cu(111) at the solid-vacuum interface. Attosecond photoemission delay measurements performed at different angles of incidence of the light allow us to study the detailed spatiotemporal dependence of the electromagnetic field distribution. Surprisingly, comparison with Monte Carlo semiclassical calculations reveals that the macroscopic Fresnel equations still properly describe the observed phase of the IR field on the Cu(111) surface on an atomic length and an attosecond time scale.
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Affiliation(s)
- M Lucchini
- Department of Physics, ETH Zurich, 8093 Zürich, Switzerland
| | - L Castiglioni
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - L Kasmi
- Department of Physics, ETH Zurich, 8093 Zürich, Switzerland
| | - P Kliuiev
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - A Ludwig
- Department of Physics, ETH Zurich, 8093 Zürich, Switzerland
| | - M Greif
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - J Osterwalder
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - M Hengsberger
- Department of Physics, University of Zurich, 8057 Zürich, Switzerland
| | - L Gallmann
- Department of Physics, ETH Zurich, 8093 Zürich, Switzerland
- Institute of Applied Physics, University of Bern, 3012 Bern, Switzerland
| | - U Keller
- Department of Physics, ETH Zurich, 8093 Zürich, Switzerland
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23
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Sabbar M, Heuser S, Boge R, Lucchini M, Carette T, Lindroth E, Gallmann L, Cirelli C, Keller U. Resonance Effects in Photoemission Time Delays. PHYSICAL REVIEW LETTERS 2015; 115:133001. [PMID: 26451550 DOI: 10.1103/physrevlett.115.133001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Indexed: 06/05/2023]
Abstract
We present measurements of single-photon ionization time delays between the outermost valence electrons of argon and neon using a coincidence detection technique that allows for the simultaneous measurement of both species under identical conditions. The analysis of the measured traces reveals energy-dependent time delays of a few tens of attoseconds with high energy resolution. In contrast to photoelectrons ejected through tunneling, single-photon ionization can be well described in the framework of Wigner time delays. Accordingly, the overall trend of our data is reproduced by recent Wigner time delay calculations. However, besides the general trend we observe resonance features occurring at specific photon energies. These features have been qualitatively reproduced and identified by a calculation using the multiconfigurational Hartree-Fock method, including the influence of doubly excited states and ionization thresholds.
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Affiliation(s)
- M Sabbar
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
| | - S Heuser
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
| | - R Boge
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
| | - M Lucchini
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
| | - T Carette
- Laboratoire de Chimie Quantique et Photophysique, CP160/09, Université Libre de Bruxelles, B 1050 Brussels, Belgium
- Physics Department, Stockholm University, AlbaNova University Center, SE-106 91 Stockholm, Sweden
| | - E Lindroth
- Physics Department, Stockholm University, AlbaNova University Center, SE-106 91 Stockholm, Sweden
| | - L Gallmann
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
- Institute of Applied Physics, University of Bern, 3012 Bern, Switzerland
| | - C Cirelli
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
| | - U Keller
- Physics Department, ETH Zurich, 8093 Zurich, Switzerland
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24
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Su J, Ni H, Jaroń-Becker A, Becker A. Time delays in two-photon ionization. PHYSICAL REVIEW LETTERS 2014; 113:263002. [PMID: 25615320 DOI: 10.1103/physrevlett.113.263002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Indexed: 06/04/2023]
Abstract
We present results of ab initio numerical simulations of time delays in two-photon ionization of the helium atom using the attosecond streaking technique. The temporal shifts in the streaking traces consist of two contributions, namely, a time delay acquired during the absorption of the two photons from the extreme-ultraviolet field and a time delay accumulated by the photoelectron after photoabsorption. In the case of a nonresonant transition, the absorption of the two photons is found to occur without time delay. In contrast, for a resonant transition a substantial absorption time delay is found, which scales linearly with the duration of the ionizing pulse. The latter can be related to the phase acquired during the transition of the electron from the initial ground state to the continuum and the influence of the streaking field on the resonant structure of the atom.
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Affiliation(s)
- Jing Su
- JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
| | - Hongcheng Ni
- JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
| | - Agnieszka Jaroń-Becker
- JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
| | - Andreas Becker
- JILA and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
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25
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Nagele S, Pazourek R, Wais M, Wachter G, Burgdörfer J. Time-resolved photoemission using attosecond streaking. ACTA ACUST UNITED AC 2014. [DOI: 10.1088/1742-6596/488/1/012004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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26
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Dixit G, Chakraborty HS, Madjet MEA. Time delay in the recoiling valence photoemission of ar endohedrally confined in C60. PHYSICAL REVIEW LETTERS 2013; 111:203003. [PMID: 24289681 DOI: 10.1103/physrevlett.111.203003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Indexed: 06/02/2023]
Abstract
The effects of confinement and electron correlations on the relative time delay between the 3s and 3p photoemissions of Ar confined endohedrally in C60 are investigated using the time-dependent local density approximation--a method that is also found to mostly agree with recent time delay measurements between the 3s and 3p subshells in atomic Ar. At energies in the neighborhood of 3p Cooper minimum, correlations with C60 electrons are found to induce opposite temporal effects in the emission of Ar 3p hybridized symmetrically versus that of Ar 3p hybridized antisymmetrically with C60. A recoil-type interaction model mediated by the confinement is found to best describe the phenomenon.
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Affiliation(s)
- Gopal Dixit
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany and Max Born Institute, Max-Born-Strasse 2A, 12489 Berlin, Germany
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27
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Lecomte JM, Kirrander A, Jungen C. Time-dependent resonant scattering: an analytical approach. J Chem Phys 2013; 139:164111. [PMID: 24182008 DOI: 10.1063/1.4825335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A time-dependent description is given of a scattering process involving a single resonance embedded in a set of flat continua. An analytical approach is presented which starts from an incident free particle wave packet and yields the Breit-Wigner cross-section formula at infinite times. We show that at intermediate times the so-called Wigner-Weisskopf approximation is equivalent to a scattering process involving a contact potential. Applications in cold-atom scattering and resonance enhanced desorption of molecules are discussed.
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Affiliation(s)
- J M Lecomte
- Laboratoire Aimé Cotton du CNRS, Ba^timent 505, Université de Paris-Sud, F-91405 Orsay, France
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28
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Stolow A. The three pillars of photo-initiated quantum molecular dynamics. Faraday Discuss 2013; 163:9-32; discussion 117-38. [DOI: 10.1039/c3fd90021e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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