1
|
Pajer V, Bohus J, Malakzadeh A, Lehotai L, Kalashnikov M, Seres I, Gilicze B, Kiss B, Börzsönyi Á, Varjú K, Szabó G, Nagymihály R. Systematic comparison of commercial devices for temporal characterization of few-cycle laser pulses in the 500-1000 nm spectral range. OPTICS EXPRESS 2024; 32:15710-15722. [PMID: 38859215 DOI: 10.1364/oe.509583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 02/06/2024] [Indexed: 06/12/2024]
Abstract
We compare multiple temporal pulse characterization techniques in three different pulse duration regimes from 15 fs to sub-5 fs, as there are no available standards yet for measuring such ultrashort pulses. To accomplish this, a versatile post-compression platform was developed, where the 100 fs near infrared pulses were post-compressed to the sub-two-cycle regime in a hybrid, three-stage configuration. After each stage, the duration of the compressed pulse was measured with the d-scan, TIPTOE and SRSI techniques and the retrieved temporal intensity profiles, spectrum and spectral phases were compared. Spectral homogeneity was also measured with an imaging spectrometer to understand the input coupling conditions of the temporal measurements. Our findings suggest that the different devices give similar results in terms of temporal intensity profile, however they are extremely sensitive to alignment and to beam quality, especially in the case of the shortest pulses. We address specific steps of measurement procedures, which paves the way towards the standardization of pulse characterization in the near future.
Collapse
|
2
|
Hariton V, Bin Wahid A, Figueira G, Fritsch K, Pronin O. Multipass spectral broadening and compression in the green spectral range. OPTICS LETTERS 2022; 47:1246-1249. [PMID: 35230338 DOI: 10.1364/ol.450200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 01/29/2022] [Indexed: 06/14/2023]
Abstract
Multipass spectral broadening and compression around 515 nm are experimentally demonstrated. A nonlinear multipass cell with a bulk medium is used to compress 250-fs pulses down to 38 fs. The same input pulses create a sufficient bandwidth for sub-20-fs pulse generation in a multipass cell with gaseous media. In both cases, the efficiency exceeds 85%. Dispersion management by reduction of the cell size and the thickness of the nonlinear medium allows an efficient generation of ultrashort pulses in the visible range and establishes a pathway for ultraviolet spectral broadening by means of multipass cells.
Collapse
|
3
|
Keil E, Malevich P, Hauer J. Achromatic frequency doubling of supercontinuum pulses for transient absorption spectroscopy. OPTICS EXPRESS 2021; 29:39042-39054. [PMID: 34809275 DOI: 10.1364/oe.442400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 10/25/2021] [Indexed: 06/13/2023]
Abstract
We present achromatic frequency doubling of supercontinuum pulses from a hollow core fiber as a technique for obtaining tunable ultrashort pulses in the near UV and blue spectral range. Pulse energies are stable on a 1.1% level, averaged over 100 000 shots. By the use of conventional optics only, we compress a 0.2 µJ pulse at a center wavelength of 475 nm to a pulse duration of 12 fs, as measured by X-FROG. We test the capabilities of the approach by employing the ASHG-pulses as a pump in a transient absorption experiment on β-carotene in solution.
Collapse
|
4
|
Hashimoto S, Takagi R, Okamura K, Yabushita A, Kobayashi T, Iwakura I. Ultrafast charge transfer dynamics in the excited state of DCM measured by a 6-fs UV pulse laser. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2021.111326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
5
|
Ko YK, Yabushita A, Kobayashi T. Primary Electronic and Vibrational Dynamics of Cytochrome c Observed by Sub-10 fs NUV Laser Pulses. J Phys Chem B 2020; 124:8249-8258. [PMID: 32852960 DOI: 10.1021/acs.jpcb.0c05959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The primary reaction mechanism of cytochrome c (Cyt c) was elucidated for two redox forms of ferric (oxidized) and ferrous (reduced) Cyt c by measuring their transient absorption (TA) spectra using a homemade sub-10 fs broadband NUV laser pulses system. The TA traces measured in the broad probe wavelength region were analyzed by the global analysis method to study the electronic dynamics. The difference of relaxation dynamics dependent on the excitation bandwidth enabled us to elucidate that the 2.5 ps component in ferrous Cyt c can be assigned to intramolecular vibration energy redistribution and not to vibrational cooling, which was not clear until this work. The temporal resolution of 10 fs observes TA signal modulation caused by the molecular vibration in the time domain, which can be used to calculate the instantaneous frequency of the molecular vibration mode. The observed vibrational dynamics has visualized that the heme structure changes in 0.8 ps for ferric Cyt c and in >1.0 ps for ferrous Cyt c. These estimated lifetimes of vibrational dynamics reflect vibrational relaxation in the ground state of ferric Cyt c and electronic transition from the S2 state to the S1 state in ferrous Cyt c, respectively.
Collapse
Affiliation(s)
- Ying Kuan Ko
- Department of Electrophysics, National Chiao-Tung University, Hsinchu 300, Taiwan, R.O.C
| | - Atsushi Yabushita
- Department of Electrophysics, National Chiao-Tung University, Hsinchu 300, Taiwan, R.O.C
| | - Takayoshi Kobayashi
- Department of Electrophysics, National Chiao-Tung University, Hsinchu 300, Taiwan, R.O.C
| |
Collapse
|
6
|
Jones T, Peters WK, Efimov A, Sandberg RL, Yarotski D, Trebino R, Bowlan P. Encoding the complete electric field of an ultraviolet ultrashort laser pulse in a near-infrared nonlinear-optical signal. OPTICS EXPRESS 2020; 28:26850-26860. [PMID: 32906951 DOI: 10.1364/oe.402025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
We introduce a variation on the cross-correlation frequency-resolved optical gating (XFROG) technique that uses a near-infrared (NIR) nonlinear-optical signal to characterize pulses in the ultraviolet (UV). Using a transient-grating XFROG beam geometry, we create a grating using two copies of the unknown UV pulse and diffract a NIR reference pulse from it. We show that, by varying the delay between the UV pulses creating the grating, the UV pulse intensity-and-phase information can be encoded into a NIR signal. We also implemented a modified generalized-projections phase-retrieval algorithm for retrieving the UV pulses from these spectrograms. We performed proof-of-principle measurements of chirped pulses and double pulses, all at 400 nm. This approach should be extendable deeper into the UV and potentially even into the extreme UV or x-ray range.
Collapse
|
7
|
Hashimoto S, Hamada K, Iwakura I, Yabushita A, Kobayashi T, Fujita H, Takeda K, Ono Y, Chikaraishi Kasuga N, Yamaguchi K. Photochemical reaction mechanisms of 4,5-dimethoxy-2-nitrobenzyl acetate analysed by a sub-10 fs near-ultraviolet pulse laser. Chem Phys 2019. [DOI: 10.1016/j.chemphys.2019.04.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
8
|
Song Y, Konar A, Sechrist R, Roy VP, Duan R, Dziurgot J, Policht V, Matutes YA, Kubarych KJ, Ogilvie JP. Multispectral multidimensional spectrometer spanning the ultraviolet to the mid-infrared. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:013108. [PMID: 30709236 DOI: 10.1063/1.5055244] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/29/2018] [Indexed: 06/09/2023]
Abstract
Multidimensional spectroscopy is the optical analog to nuclear magnetic resonance, probing dynamical processes with ultrafast time resolution. At optical frequencies, the technical challenges of multidimensional spectroscopy have hindered its progress until recently, where advances in laser sources and pulse-shaping have removed many obstacles to its implementation. Multidimensional spectroscopy in the visible and infrared (IR) regimes has already enabled respective advances in our understanding of photosynthesis and the structural rearrangements of liquid water. A frontier of ultrafast spectroscopy is to extend and combine multidimensional techniques and frequency ranges, which have been largely restricted to operating in the distinct visible or IR regimes. By employing two independent amplifiers seeded by a single oscillator, it is straightforward to span a wide range of time scales (femtoseconds to seconds), all of which are often relevant to the most important energy conversion and catalysis problems in chemistry, physics, and materials science. Complex condensed phase systems have optical transitions spanning the ultraviolet (UV) to the IR and exhibit dynamics relevant to function on time scales of femtoseconds to seconds and beyond. We describe the development of the Multispectral Multidimensional Nonlinear Spectrometer (MMDS) to enable studies of dynamical processes in atomic, molecular, and material systems spanning femtoseconds to seconds, from the UV to the IR regimes. The MMDS employs pulse-shaping methods to provide an easy-to-use instrument with an unprecedented spectral range that enables unique combination spectroscopies. We demonstrate the multispectral capabilities of the MMDS on several model systems.
Collapse
Affiliation(s)
- Yin Song
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Arkaprabha Konar
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Riley Sechrist
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Ved Prakash Roy
- Department of Chemistry, University of Michigan, 930 N University Ave., Ann Arbor, Michigan 48109, USA
| | - Rong Duan
- Department of Chemistry, University of Michigan, 930 N University Ave., Ann Arbor, Michigan 48109, USA
| | - Jared Dziurgot
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Veronica Policht
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Yassel Acosta Matutes
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| | - Kevin J Kubarych
- Department of Chemistry, University of Michigan, 930 N University Ave., Ann Arbor, Michigan 48109, USA
| | - Jennifer P Ogilvie
- Department of Physics, University of Michigan, 450 Church St., Ann Arbor, Michigan 48109, USA
| |
Collapse
|
9
|
Hashimoto S, Yabushita A, Kobayashi T, Okamura K, Iwakura I. Direct observation of the change in transient molecular structure of 9,9′-bianthryl using a 10 fs pulse UV laser. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2017.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
10
|
Universal route to optimal few- to single-cycle pulse generation in hollow-core fiber compressors. Sci Rep 2018; 8:2256. [PMID: 29396420 PMCID: PMC5797182 DOI: 10.1038/s41598-018-20580-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 01/22/2018] [Indexed: 11/08/2022] Open
Abstract
Gas-filled hollow-core fiber (HCF) pulse post-compressors generating few- to single-cycle pulses are a key enabling tool for attosecond science and ultrafast spectroscopy. Achieving optimum performance in this regime can be extremely challenging due to the ultra-broad bandwidth of the pulses and the need of an adequate temporal diagnostic. These difficulties have hindered the full exploitation of HCF post-compressors, namely the generation of stable and high-quality near-Fourier-transform-limited pulses. Here we show that, independently of conditions such as the type of gas or the laser system used, there is a universal route to obtain the shortest stable output pulse down to the single-cycle regime. Numerical simulations and experimental measurements performed with the dispersion-scan technique reveal that, in quite general conditions, post-compressed pulses exhibit a residual third-order dispersion intrinsic to optimum nonlinear propagation within the fiber, in agreement with measurements independently performed in several laboratories around the world. The understanding of this effect and its adequate correction, e.g. using simple transparent optical media, enables achieving high-quality post-compressed pulses with only minor changes in existing setups. These optimized sources have impact in many fields of science and technology and should enable new and exciting applications in the few- to single-cycle pulse regime.
Collapse
|
11
|
Silva F, Alonso B, Holgado W, Romero R, Román JS, Jarque EC, Koop H, Pervak V, Crespo H, Sola ÍJ. Strategies for achieving intense single-cycle pulses with in-line post-compression setups. OPTICS LETTERS 2018; 43:337-340. [PMID: 29328280 DOI: 10.1364/ol.43.000337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 12/14/2017] [Indexed: 06/07/2023]
Abstract
Intense few- and single-cycle pulses are powerful tools in different fields of science Today, third- and higher-order terms in the remnant spectral phase of the pulses remain a major obstacle for obtaining high-quality few- and single-cycle pulses from in-line post-compression setups. In this Letter, we show how input pulse shaping can successfully be applied to standard post-compression setups to minimize the occurrence of high-order phase components during nonlinear propagation and to directly obtain pulses with durations down to 3 fs. Furthermore, by combining this pulse shaping of the input pulse with new-generation broadband chirped mirrors and material addition for remnant third-order phase correction, pulses down to 2.2 fs duration have been measured.
Collapse
|
12
|
Hutchison CD, van Thor JJ. Populations and coherence in femtosecond time resolved X-ray crystallography of the photoactive yellow protein. INT REV PHYS CHEM 2017. [DOI: 10.1080/0144235x.2017.1276726] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
| | - Jasper J. van Thor
- Molecular Biophysics, Imperial College London, South Kensington Campus, London, UK
| |
Collapse
|
13
|
Chang HT, Zürch M, Kraus PM, Borja LJ, Neumark DM, Leone SR. Simultaneous generation of sub-5-femtosecond 400 nm and 800 nm pulses for attosecond extreme ultraviolet pump-probe spectroscopy. OPTICS LETTERS 2016; 41:5365-5368. [PMID: 27842133 DOI: 10.1364/ol.41.005365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Few-cycle laser pulses with wavelengths centered at 400 nm and 800 nm are simultaneously obtained through wavelength separation of ultrashort, spectrally broadened Vis-NIR laser pulses spanning 350-1100 nm wavelengths. The 400 nm and 800 nm pulses are separately compressed, yielding pulses with 4.4 fs and 3.8 fs duration, respectively. The pulse energy exceeds 5 μJ for the 400 nm pulses and 750 μJ for the 800 nm pulses. Intense 400 nm few-cycle pulses have a broad range of applications in nonlinear optical spectroscopy, which include the study of photochemical dynamics, semiconductors, and photovoltaic materials on few-femtosecond to attosecond time scales. The ultrashort 400 nm few-cycle pulses generated here not only extend the spectral range of the optical pulse for NIR-XUV attosecond pump-probe spectroscopy but also pave the way for two-color, three-pulse, multidimensional optical-XUV spectroscopy experiments.
Collapse
|
14
|
Gueye M, Nillon J, Crégut O, Léonard J. Broadband UV-Vis vibrational coherence spectrometer based on a hollow fiber compressor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:093109. [PMID: 27782548 DOI: 10.1063/1.4962699] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We describe a broadband transient absorption (TA) spectrometer devised to excite and probe, in the blue to UV range, vibrational coherence dynamics in organic molecules in condensed phase. A 800-nm Ti:Sa amplifier and a hollow fiber compressor are used to generate a 6-fs short pulse at 1 kHz. Broadband sum frequency generation with the fundamental pulse is implemented to produce a 400-nm, 8-fs Fourier limited short pulse. A UV-Vis white-light supercontinuum is implemented as a probe with intensity self-referencing to achieve a shot-noise-limited sensitivity. Rapid scanning of the pump-probe delay is shown very efficient in suppressing the noise resulting from low-frequency pump intensity fluctuations. Using either of the 800-nm or 400-nm broadband pulses as the pump for TA spectroscopy of organic molecules in solution, we resolve oscillatory signals down to the 320 nm probing wavelength with a 3200 cm-1 FWHM bandwidth. Their Fourier transformation reveals the corresponding molecular vibrational spectra. Finally, we demonstrate the use of this setup as a vibrational coherence spectrometer for the investigation of the vibrational dynamics accompanying the sub-ps C=C photoisomerization of a retinal-like molecular switch through a conical intersection.
Collapse
Affiliation(s)
- Moussa Gueye
- Institut de Physique et Chimie des Matériaux de Strasbourg & Labex NIE, Université de Strasbourg, CNRS UMR 7504, 23 rue du Loess, Strasbourg 67034, France
| | - Julien Nillon
- Institut de Physique et Chimie des Matériaux de Strasbourg & Labex NIE, Université de Strasbourg, CNRS UMR 7504, 23 rue du Loess, Strasbourg 67034, France
| | - Olivier Crégut
- Institut de Physique et Chimie des Matériaux de Strasbourg & Labex NIE, Université de Strasbourg, CNRS UMR 7504, 23 rue du Loess, Strasbourg 67034, France
| | - Jérémie Léonard
- Institut de Physique et Chimie des Matériaux de Strasbourg & Labex NIE, Université de Strasbourg, CNRS UMR 7504, 23 rue du Loess, Strasbourg 67034, France
| |
Collapse
|
15
|
Al Haddad A, Chauvet A, Ojeda J, Arrell C, van Mourik F, Auböck G, Chergui M. Set-up for broadband Fourier-transform multidimensional electronic spectroscopy. OPTICS LETTERS 2015; 40:312-315. [PMID: 25680035 DOI: 10.1364/ol.40.000312] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a compact passively phase-stabilized ultra-broadband 2D Fourier transform setup. A gas (argon)-filled hollow core fiber pumped by an amplified Ti:Al2O3 laser is used as a light source providing spectral range spanning from 420 to 900 nm. Sub-10-fs pulses were obtained using a deformable mirror-based pulse shaper. We probe the nonlinear response of Rhodamine 101 using 90 nm bandwidth and resolve vibrational coherences of 150 fs period in the ground state.
Collapse
|
16
|
Neukirch AJ, Neumark DM, Kling MF, Prezhdo OV. Resolving multi-exciton generation by attosecond spectroscopy. OPTICS EXPRESS 2014; 22:26285-26293. [PMID: 25401661 DOI: 10.1364/oe.22.026285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We propose an experimentally viable attosecond transient absorption spectroscopy scheme to resolve controversies regarding multiexciton (ME) generation in nanoscale systems. Absence of oscillations indicates that light excites single excitons, and MEs are created by incoherent impact ionization. An oscillation indicates the coherent mechanism, involving excitation of superpositions of single and MEs. The oscillation decay, ranging from 5 fs at ambient temperature to 20 fs at 100 K, gives the elastic exciton-phonon scattering time. The signal is best observed with multiple-cycle pump pulses.
Collapse
|
17
|
Liu J, Yabushita A, Taniguchi S, Chosrowjan H, Imamoto Y, Sueda K, Miyanaga N, Kobayashi T. Ultrafast Time-Resolved Pump–Probe Spectroscopy of PYP by a Sub-8 fs Pulse Laser at 400 nm. J Phys Chem B 2013; 117:4818-26. [DOI: 10.1021/jp4001016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jun Liu
- Advanced Ultrafast Laser Research
Center, University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 Japan
- State Key Laboratory of High
Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
- Core Research for Evolutional
Science and Technology (CREST), Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Atsushi Yabushita
- Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road,
Hsinchu 300, Taiwan
| | - Seiji Taniguchi
- Institute
for Laser Technology, Osaka University,
Yamadaoka 2-6, Suita Osaka, 565-0871
Japan
| | - Haik Chosrowjan
- Institute
for Laser Technology, Osaka University,
Yamadaoka 2-6, Suita Osaka, 565-0871
Japan
| | - Yasushi Imamoto
- Department of Biophysics,
Graduate
School of Science, Kyoto University, Kitashirakawa-Oiwake,
Sakyo, Kyoto 606-8502 Japan
| | - Keiichi Sueda
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
| | - Noriaki Miyanaga
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
| | - Takayoshi Kobayashi
- Advanced Ultrafast Laser Research
Center, University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 Japan
- Core Research for Evolutional
Science and Technology (CREST), Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
- Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road,
Hsinchu 300, Taiwan
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
| |
Collapse
|
18
|
Lincoln CN, Fitzpatrick AE, van Thor JJ. Photoisomerisation quantum yield and non-linear cross-sections with femtosecond excitation of the photoactive yellow protein. Phys Chem Chem Phys 2012; 14:15752-64. [PMID: 23090503 DOI: 10.1039/c2cp41718a] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The quantum yield of photoisomerisation of the photoactive yellow protein (PYP) strongly depends on peak power and wavelength with femtosecond optical excitation. Using systematic power titrations and addition of second order dispersion resulting in 140, 300 and 600 fs pulse durations, the one and multi-photon cross-sections at 400, 450 and 490 nm have been assessed from transient absorption spectroscopy and additionally the Z-scan technique. Applying a target model that incorporates photoselection theory, estimates for the cross-sections for stimulated emission and absorption of the first excited state, the amount of ultrafast internal conversion and the underlying species associated dynamics have been determined. The final quantum yields for photoisomerisation were found to be 0.06, 0.14-0.19 and 0.02 for excitation wavelengths 400, 450 and 490 nm and found to increase with increasing pulse durations. Transient absorption measurements and Z-scan measurements at 450 nm, coinciding with the maximum wavelength of the ground state absorption, indicate that the photochemical quantum yield is intrinsically limited by an ultrafast internal conversion reaction as well as by stimulated emission cross-section. With excitation at 400 nm photoisomerisation quantum yield is further significantly limited by competing multi-photon excitation into excited state absorption at 385 nm previously proposed to result in photoionisation. With excitation at 490 nm the photoisomerisation quantum yield is predominantly limited further by the significantly higher stimulated emission cross-section compared to ground state cross-section as well as multi-photon processes. In addition to photoionisation, a second product of multi-photon excitation is identified and characterised by an induced absorption at 500 nm and a time constant of 2 ps for relaxation. With power densities up to 138 GW cm(-2) the measurements have not provided indication for coherent multi-photon absorption of PYP. In the saturation regime with 450 nm excitation, the limit for the photoisomerisation quantum yield was found to be 0.14-0.19 and the excited state absorption cross-section 6.1 × 10(-17) cm(2) or 0.36 times the ground state cross-section of 1.68 × 10(-16) cm(2) per molecule. This places a fundamental restriction on the maximum populations and sample penetration that may be achieved for instance in femtosecond pump-probe experiments with molecular crystals of PYP.
Collapse
Affiliation(s)
- Craig N Lincoln
- Imperial College London, Division of Molecular Biosciences, South Kensington campus, SW7 2AZ, London, UK
| | | | | |
Collapse
|
19
|
Kida Y, Okamura K, Liu J, Kobayashi T. Sub-10-fs deep-ultraviolet light source with stable power and spectrum. APPLIED OPTICS 2012; 51:6403-6410. [PMID: 22968281 DOI: 10.1364/ao.51.006403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 08/15/2012] [Indexed: 06/01/2023]
Abstract
In some applications of ultrafast spectroscopy that employ sub-10-fs pulses, the pulse spectrum and power need to be stable for several tens of minutes. In this study, we generate sub-10-fs deep-ultraviolet (DUV) pulses with such stabilities by chirped-pulse four-wave mixing. A power fluctuation of less than 3% rms was realized by employing stabilization schemes that employ a power stabilizer. The pulses generated in this study have been applied to transient absorption spectroscopy in the DUV with a sub-10-fs time resolution [Phys. Chem. Chem. Phys.14, 6200 (2012).10.1039/c2cp23649d]. This sub-10-fs DUV source has a similar performance to widely used noncollinear optical parametric amplifiers.
Collapse
Affiliation(s)
- Yuichiro Kida
- Advanced Ultrafast Laser Research Center, University of Electro-Communications, Chofugaoka, Chofu, Tokyo, Japan
| | | | | | | |
Collapse
|
20
|
Kobayashi T, Kida Y. Ultrafast spectroscopy with sub-10 fs deep-ultraviolet pulses. Phys Chem Chem Phys 2012; 14:6200-10. [PMID: 22354017 DOI: 10.1039/c2cp23649d] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Time-resolved transient absorption spectroscopy with sub-9 fs ultrashort laser pulses in the deep-ultraviolet (DUV) region is reported for the first time. Single 8.7 fs DUV pulses with a spectral range of 255-290 nm are generated by a chirped-pulse four-wave mixing technique for use as pump and probe pulses. Electronic excited state and vibrational dynamics are simultaneously observed for an aqueous solution of thymine over the full spectral range using a 128-channel lock-in detector. Vibrational modes of the electronic ground state and excited states can be observed as well as the decay dynamics of the electronic excited state. Information on the initial phase of the vibrational modes is extracted from the measured difference absorbance trace, which contains oscillatory structures arising from the vibrational modes of the molecule. Along with other techniques such as time-resolved infrared spectroscopy, spectroscopy with sub-9 fs DUV pulses is expected to contribute to a detailed understanding of the photochemical dynamics of biologically significant molecules that absorb in the DUV region such as DNA and amino acids.
Collapse
Affiliation(s)
- Takayoshi Kobayashi
- Advanced Ultrafast Laser Research Center, University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan.
| | | |
Collapse
|