1
|
Forbes R, Hockett P, Lausten R. Efficient generation of the 7th harmonic of Ti:sapphire (114.6 nm) vacuum ultraviolet pulses with 60 fs duration by non-collinear four-wave mixing in argon. OPTICS LETTERS 2022; 47:2410-2413. [PMID: 35561363 DOI: 10.1364/ol.457070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/11/2022] [Indexed: 06/15/2023]
Abstract
The recent advances in femtosecond vacuum UV (VUV) pulse generation, pioneered by the work of Noack et al., has enabled new experiments in ultrafast time-resolved spectroscopy. Expanding on this work, we report the generation of 60 fs VUV pulses at the 7th harmonic of Ti:sapphire with more than 50 nJ of pulse energy at a repetition rate of 1 kHz. The 114.6 nm pulses are produced using non-collinear four-wave difference-frequency mixing in argon. The non-collinear geometry increases the phase-matching pressure, and results in a conversion efficiency of ∼10-3 from the 200 nm pump beam. The VUV pulses are pre-chirp-compensated for material dispersion with xenon, which has negative dispersion in this wavelength range, thus allowing almost transform-limited pulses to be delivered to the experimental chamber.
Collapse
|
2
|
Piteša T, Sapunar M, Ponzi A, Gelin MF, Došlić N, Domcke W, Decleva P. Combined Surface-Hopping, Dyson Orbital, and B-Spline Approach for the Computation of Time-Resolved Photoelectron Spectroscopy Signals: The Internal Conversion in Pyrazine. J Chem Theory Comput 2021; 17:5098-5109. [PMID: 34269561 DOI: 10.1021/acs.jctc.1c00396] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A computational protocol for simulating time-resolved photoelectron signals of medium-sized molecules is presented. The procedure is based on a trajectory surface-hopping description of the excited-state dynamics and a combined Dyson orbital and multicenter B-spline approach for the computation of cross sections and asymmetry parameters. The accuracy of the procedure has been illustrated for the case of ultrafast internal conversion of gas-phase pyrazine excited to the 1B2u(ππ*) state. The simulated spectra and the asymmetry map are compared to the experimental data, and a very good agreement was obtained without applying any energy-dependent rescaling or broadening. An interesting side result of this work is the finding that the signature of the 1Au(nπ*) state is indistinguishable from that of the 1B3u(nπ*) state in the time-resolved photoelectron spectrum. By locating four symmetrically equivalent minima on the lowest-excited (S1) adiabatic potential energy surface of pyrazine, we revealed the strong vibronic coupling of the 1Au(nπ*) and 1B3u(nπ*) states near the S1 ← S0 band origin.
Collapse
Affiliation(s)
- Tomislav Piteša
- Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Marin Sapunar
- Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Aurora Ponzi
- Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Maxim F Gelin
- School of Science, Hangzhou Dianzi University, Hangzhou 310018, China
| | - Nađa Došlić
- Department of Physical Chemistry, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Wolfgang Domcke
- Department of Chemistry, Technical University of Munich, D-85747 Garching, Germany
| | - Piero Decleva
- Dipartimento di Scienze Chimiche, Università di Trieste, I-34127 Trieste, Italy
| |
Collapse
|
3
|
Suzuki T. Spiers Memorial Lecture: Introduction to ultrafast spectroscopy and imaging of photochemical reactions. Faraday Discuss 2021; 228:11-38. [PMID: 33876168 DOI: 10.1039/d1fd00015b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A brief overview is presented on ultrafast spectroscopy and imaging of photochemical reactions by highlighting several experimental studies reported in the last five years. A particular focus is placed on new experiments performed using high-order harmonic generation, X-ray free electron lasers, and relativistic electron beams. Exploration of fundamental chemical reaction dynamics using these advanced experimental methodologies is in an early stage, and exciting new research opportunities await in this rapidly expanding and advancing research field. At the same time, there is no experimental methodology that provides all aspects of the electronic and structural dynamics in a single experiment, and investigations using different methodologies with various perspectives need to be considered in a comprehensive manner.
Collapse
Affiliation(s)
- Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
| |
Collapse
|
4
|
Karashima S, Suzuki YI, Suzuki T. Ultrafast Extreme Ultraviolet Photoelectron Spectroscopy of Nonadiabatic Photodissociation of CS 2 from 1B 2 ( 1Σ u+) State: Product Formation via an Intermediate Electronic State. J Phys Chem Lett 2021; 12:3755-3761. [PMID: 33844534 DOI: 10.1021/acs.jpclett.1c00864] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We studied nonadiabatic dissociation of CS2 from the 1B2 (1Σu+) state using ultrafast extreme ultraviolet photoelectron spectroscopy. A deep UV (200 nm) laser using the filamentation four-wave mixing method and an extreme UV (21.7 eV) laser using the high-order harmonic generation method were employed to achieve the pump-probe laser cross-correlation time of 48 fs. Spectra measured with a high signal-to-noise ratio revealed clear dynamical features of vibrational wave packet motion in the 1B2 state; its electronic decay to lower electronic state(s) within 630 fs; and dissociation into S(1D2), S(3PJ), and CS fragments within 300 fs. The results suggest that both singlet and triplet dissociation occur via intermediate electronic state(s) produced by electronic relaxation from the 1B2 (1Σu+) state.
Collapse
Affiliation(s)
- Shutaro Karashima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo, Kyoto 606-8502, Japan
| | - Yoshi-Ichi Suzuki
- School of Medical Technology, Health Sciences University of Hokkaido, 1757 Kanazawa, Tobetsucho, Ishikari, Hokkaido 061-0293, Japan
| | - Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo, Kyoto 606-8502, Japan
| |
Collapse
|
5
|
Huang WH, Zhao Y, Kusama S, Kumaki F, Luo CW, Fuji T. Generation of sub-half-cycle 10 µm pulses through filamentation at kilohertz repetition rates. OPTICS EXPRESS 2020; 28:36527-36543. [PMID: 33379745 DOI: 10.1364/oe.408342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 11/07/2020] [Indexed: 06/12/2023]
Abstract
We have experimentally demonstrated the generation of sub-half-cycle phase-stable pulses with the carrier wavelength of 10.2 µm through two-color filamentation in nitrogen. The carrier-envelope phase (CEP) of the MIR pulse is passively stabilized and controlled by the attosecond time delay between the two-color input pulses. The duration of the MIR pulse is 13.7 fs, which corresponds to 0.402 cycles. The absolute value of the CEP of the generated sub-half-cycle pulse is consistent with a simple four-wave difference frequency generation model. We have also found that the 10 kHz repetition rate of the light source causes the fluctuation of the pulse energy on a few hundred millisecond time scale.
Collapse
|
6
|
Edwards MR, Mikhailova JM. The X-Ray Emission Effectiveness of Plasma Mirrors: Reexamining Power-Law Scaling for Relativistic High-Order Harmonic Generation. Sci Rep 2020; 10:5154. [PMID: 32198482 PMCID: PMC7083899 DOI: 10.1038/s41598-020-61255-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 02/19/2020] [Indexed: 11/20/2022] Open
Abstract
Ultrashort pulsed lasers provide uniquely detailed access to the ultrafast dynamics of physical, chemical, and biological systems, but only a handful of wavelengths are directly produced by solid-state lasers, necessitating efficient high-power frequency conversion. Relativistic plasma mirrors generate broadband power-law spectra, that may span the gap between petawatt-class infrared laser facilities and x-ray free-electron lasers; despite substantial theoretical work the ultimate efficiency of this relativistic high-order-harmonic generation remains unclear. We show that the coherent radiation emitted by plasma mirrors follows a power-law distribution of energy over frequency with an exponent that, even in the ultrarelativistic limit, strongly depends on the ratio of laser intensity to plasma density and exceeds the frequently quoted value of -8/3 over a wide range of parameters. The coherent synchrotron emission model, when adequately corrected for the finite width of emitting electron bunches, is not just valid for p-polarized light and thin foil targets, but generally describes relativistic harmonic generation, including at normal incidence and with finite-gradient plasmas. Our numerical results support the ω-4/3 scaling of the synchrotron emission model as a limiting efficiency of the process under most conditions. The highest frequencies that can be generated with this scaling are usually restricted by the width of the emitting electron bunch rather than the Lorentz factor of the fastest electrons. The theoretical scaling relations developed here suggest, for example, that with a 20-PW 800-nm driving laser, 1 TW/harmonic can be produced for 1-keV photons.
Collapse
Affiliation(s)
- Matthew R Edwards
- Princeton University, Department of Mechanical and Aerospace Engineering, Princeton, New Jersey, 08544, USA.
| | - Julia M Mikhailova
- Princeton University, Department of Mechanical and Aerospace Engineering, Princeton, New Jersey, 08544, USA.
| |
Collapse
|
7
|
Affiliation(s)
- Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-Ku, Kyoto 606-8502,
Japan
| |
Collapse
|
8
|
Uenishi R, Horio T, Suzuki T. Time-Resolved Photoelectron Imaging of Acetone with 9.3 eV Photoexcitation. J Phys Chem A 2019; 123:6848-6853. [PMID: 31314525 DOI: 10.1021/acs.jpca.9b05179] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ultrafast electronic relaxation following 9.3 eV photoexcitation of gaseous acetone was investigated with time-resolved photoelectron imaging spectroscopy. An intense photoionization signal due to a transition from the 41A1(π,π*) state to the D1(π-1) cationic state diminishes within 50 fs, owing to vibrational wave packet motion leaving our observation energy window. Additional photoionization signals were assigned to transitions from Rydberg states with principal quantum numbers of 3-8 to the D0(n-1) cationic state, created by strong vibronic couplings with the bright 41A1(π,π*) state. The deactivation processes of the 41A1(π,π*) and Rydberg states are discussed based on their decay profiles obtained from a time-energy map of photoelectron kinetic energy distributions.
Collapse
Affiliation(s)
- Ryuta Uenishi
- Department of Chemistry, Graduate School of Science , Kyoto University , Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 , Japan
| | - Takuya Horio
- Department of Chemistry, Graduate School of Science , Kyoto University , Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 , Japan
| | - Toshinori Suzuki
- Department of Chemistry, Graduate School of Science , Kyoto University , Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502 , Japan
| |
Collapse
|
9
|
Ultraviolet Transient Absorption Spectrometer with Sub-20-fs Time Resolution. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8060989] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
10
|
Bellshaw D, Horke DA, Smith AD, Watts HM, Jager E, Springate E, Alexander O, Cacho C, Chapman RT, Kirrander A, Minns RS. Ab-initio surface hopping and multiphoton ionisation study of the photodissociation dynamics of CS2. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.058] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
11
|
Nishitani J, West CW, Higashimura C, Suzuki T. Time-resolved photoelectron spectroscopy of polyatomic molecules using 42-nm vacuum ultraviolet laser based on high harmonics generation. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.07.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
12
|
Horio T, Spesyvtsev R, Furumido Y, Suzuki T. Real-time detection of S(1D2) photofragments produced from the 1B2(1Σu+) state of CS2 by vacuum ultraviolet photoelectron imaging using 133 nm probe pulses. J Chem Phys 2017; 147:013932. [DOI: 10.1063/1.4982219] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
13
|
Horio T, Spesyvtsev R, Nagashima K, Ingle RA, Suzuki YI, Suzuki T. Full observation of ultrafast cascaded radiationless transitions from S2(ππ∗) state of pyrazine using vacuum ultraviolet photoelectron imaging. J Chem Phys 2016; 145:044306. [DOI: 10.1063/1.4955296] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Takuya Horio
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Roman Spesyvtsev
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Kazuki Nagashima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Rebecca A. Ingle
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Yoshi-ichi Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| | - Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-Ku, Kyoto 606-8502, Japan
| |
Collapse
|
14
|
Horio T, Suzuki YI, Suzuki T. Ultrafast photodynamics of pyrazine in the vacuum ultraviolet region studied by time-resolved photoelectron imaging using 7.8-eV pulses. J Chem Phys 2016; 145:044307. [DOI: 10.1063/1.4955298] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
15
|
Spesyvtsev R, Horio T, Suzuki YI, Suzuki T. Excited-state dynamics of furan studied by sub-20-fs time-resolved photoelectron imaging using 159-nm pulses. J Chem Phys 2015; 143:014302. [PMID: 26156478 DOI: 10.1063/1.4922904] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The excited-state dynamics of furan were studied by time-resolved photoelectron imaging using a sub-20-fs deep UV (198 nm) and vacuum UV (159 nm) light source. The 198- and 159-nm pulses produce photoionization signals in both pump-probe and probe-pump pulse sequences. When the 198-nm pulse precedes the 159-nm pulse, it creates the (1)A2(3s) Rydberg and (1)B2(ππ(∗)) valence states, and the former decays exponentially with a time constant of about 20 fs whereas the latter exhibits more complex wave-packet dynamics. When the 159-nm pulse precedes the 198-nm pulse, a wave packet is created on the (1)A1(ππ(∗)) valence state, which rapidly disappears from the observation window owing to structural deformation. The 159-nm photoexcitation also creates the 3s and 3px,y Rydberg states non-adiabatically.
Collapse
Affiliation(s)
- R Spesyvtsev
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - T Horio
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Y-I Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - T Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| |
Collapse
|
16
|
Bartlett NCM, Ogi Y, Suzuki T. Ultrafast Photoelectron Imaging Using Tunable UV and Vacuum UV Pulses. CHEM LETT 2015. [DOI: 10.1246/cl.150177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | | | - Toshinori Suzuki
- RIKEN Center for Advanced Photonics, RIKEN
- CREST, Japan Science and Technology Agency
- Department of Chemistry, Graduate School of Science, Kyoto University
| |
Collapse
|
17
|
Spesyvtsev R, Horio T, Suzuki YI, Suzuki T. Observation of the wavepacket dynamics on the 1B2(1Σu+) state of CS2 by sub-20 fs photoelectron imaging using 159 nm probe pulses. J Chem Phys 2015; 142:074308. [DOI: 10.1063/1.4907749] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|