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Wang P, He L, Deng Y, Sun S, Lan P, Lu P. Unveiling Nonsecular Collisional Dissipation of Molecular Alignment. PHYSICAL REVIEW LETTERS 2024; 133:033202. [PMID: 39094146 DOI: 10.1103/physrevlett.133.033202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/17/2024] [Accepted: 06/18/2024] [Indexed: 08/04/2024]
Abstract
We conducted a joint theoretical and experimental study to investigate the collisional dissipation of molecular alignment. By comparing experimental measurements to the quantum simulations, the nonsecular effect in the collision dissipation of molecular alignment was unveiled from the gas-density-dependent decay rates of the molecular alignment revival signals. Different from the conventional perspective that the nonsecular collisional effect rapidly fades within the initial few picoseconds following laser excitation, our simulations of the time-dependent decoherence process demonstrated that this effect can last for tens of picoseconds in the low-pressure regime. This extended timescale allows for the distinct identification of the nonsecular effect from molecular alignment signals. Our findings present the pioneering evidence that nonsecular molecular collisional dissipation can endure over an extended temporal span, challenging established concepts and strengthening our understanding of molecular dynamics within dissipative environments.
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2
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Qiang J, Zhou L, Peng Y, Yu C, Lu P, Pan S, Lu C, Chen G, Lu R, Zhang W, Wu J. Femtosecond Collisional Dissipation of Vibrating D_{2}^{+} in Helium Nanodroplets. PHYSICAL REVIEW LETTERS 2024; 132:103201. [PMID: 38518314 DOI: 10.1103/physrevlett.132.103201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 02/05/2024] [Indexed: 03/24/2024]
Abstract
We explored the collision-induced vibrational decoherence of singly ionized D_{2} molecules inside a helium nanodroplet. By using the pump-probe reaction microscopy with few-cycle laser pulses, we captured in real time the collision-induced ultrafast dissipation of vibrational nuclear wave packet dynamics of D_{2}^{+} ion embedded in the droplet. Because of the strong coupling of excited molecular cations with the surrounding solvent, the vibrational coherence of D_{2}^{+} in the droplet interior only lasts for a few vibrational periods and completely collapses within 140 fs. The observed ultrafast coherence loss is distinct from that of isolated D_{2}^{+} in the gas phase, where the vibrational coherence persists for a long time with periodic quantum revivals. Our findings underscore the crucial role of ultrafast collisional dissipation in shaping the molecular decoherence and solvation dynamics during solution chemical reactions, particularly when the solute molecules are predominantly in ionic states.
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Affiliation(s)
- Junjie Qiang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
- School of Physics and Microelectronics Key Laboratory of Materials Physics of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
| | - Lianrong Zhou
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Yigeng Peng
- Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Chao Yu
- Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Peifen Lu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Shengzhe Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Chenxu Lu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Gang Chen
- School of Physics and Microelectronics Key Laboratory of Materials Physics of Ministry of Education, Zhengzhou University, Zhengzhou 450001, China
| | - Ruifeng Lu
- Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Wenbin Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Jian Wu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
- Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing 401121, China
- CAS Center for Excellence in Ultra-Intense Laser Science, Shanghai 201800, China
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3
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Bournazel M, Ma J, Billard F, Hertz E, Wu J, Boulet C, Faucher O, Hartmann JM. Quantum modeling, beyond secularity, of the collisional dissipation of molecular alignment using the energy-corrected sudden approximation. J Chem Phys 2023; 158:2887565. [PMID: 37125716 DOI: 10.1063/5.0150002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/12/2023] [Indexed: 05/02/2023] Open
Abstract
We propose a Markovian quantum model for the time dependence of the pressure-induced decoherence of rotational wave packets of gas-phase molecules beyond the secular approximation. It is based on a collisional relaxation matrix constructed using the energy-corrected sudden approximation, which improves the previously proposed infinite order sudden one by taking the molecule rotation during collisions into account. The model is tested by comparisons with time-domain measurements of the pressure-induced decays of molecular-axis alignment features (revivals and echoes) for HCl and CO2 gases, pure and diluted in He. For the Markovian systems HCl-He and CO2-He, the comparisons between computed and measured data demonstrate the robustness of our approach, even when the secular approximation largely breaks down. In contrast, significant differences are obtained in the cases of pure HCl and CO2, for which the model underestimates the decay rate of the alignment at short times. This result is attributed to the non-Markovianity of HCl-HCl and CO2-CO2 interactions and the important contribution of those collisions that are ongoing at the time when the system is excited by the aligning laser pulse.
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Affiliation(s)
- M Bournazel
- Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, 21078 Dijon, France
| | - J Ma
- Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, 21078 Dijon, France
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - F Billard
- Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, 21078 Dijon, France
| | - E Hertz
- Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, 21078 Dijon, France
| | - J Wu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - C Boulet
- Institut des Sciences Moléculaires d'Orsay, CNRS, Université Paris-Saclay, Orsay F-91405, France
| | - O Faucher
- Laboratoire Interdisciplinaire CARNOT de Bourgogne, UMR 6303 CNRS-Université de Bourgogne, BP 47870, 21078 Dijon, France
| | - J-M Hartmann
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Sorbonne Université, Ecole Normale Supérieure, Université PSL, F-91120 Palaiseau, France
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4
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Mazza F, Thornquist O, Castellanos L, Butterworth T, Richard C, Boudon V, Bohlin A. The ro-vibrational ν 2 mode spectrum of methane investigated by ultrabroadband coherent Raman spectroscopy. J Chem Phys 2023; 158:094201. [PMID: 36889980 DOI: 10.1063/5.0138803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023] Open
Abstract
We present the first experimental application of coherent Raman spectroscopy (CRS) on the ro-vibrational ν2 mode spectrum of methane (CH4). Ultrabroadband femtosecond/picosecond (fs/ps) CRS is performed in the molecular fingerprint region from 1100 to 2000 cm-1, employing fs laser-induced filamentation as the supercontinuum generation mechanism to provide the ultrabroadband excitation pulses. We introduce a time-domain model of the CH4 ν2 CRS spectrum, including all five ro-vibrational branches allowed by the selection rules Δv = 1, ΔJ = 0, ±1, ±2; the model includes collisional linewidths, computed according to a modified exponential gap scaling law and validated experimentally. The use of ultrabroadband CRS for in situ monitoring of the CH4 chemistry is demonstrated in a laboratory CH4/air diffusion flame: CRS measurements in the fingerprint region, performed across the laminar flame front, allow the simultaneous detection of molecular oxygen (O2), carbon dioxide (CO2), and molecular hydrogen (H2), along with CH4. Fundamental physicochemical processes, such as H2 production via CH4 pyrolysis, are observed through the Raman spectra of these chemical species. In addition, we demonstrate ro-vibrational CH4 v2 CRS thermometry, and we validate it against CO2 CRS measurements. The present technique offers an interesting diagnostics approach to in situ measurement of CH4-rich environments, e.g., in plasma reactors for CH4 pyrolysis and H2 production.
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Affiliation(s)
- Francesco Mazza
- Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands
| | - Ona Thornquist
- Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands
| | - Leonardo Castellanos
- Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands
| | - Thomas Butterworth
- Faculty of Science and Engineering, Maastricht University, Paul Henri Spaaklaan 1, 6229 GS Maastricht, The Netherlands
| | - Cyril Richard
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - Vincent Boudon
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Université Bourgogne Franche-Comté, 9 Avenue Alain Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - Alexis Bohlin
- Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, The Netherlands
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5
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Qiang J, Zhou L, Lu P, Lin K, Ma Y, Pan S, Lu C, Jiang W, Sun F, Zhang W, Li H, Gong X, Averbukh IS, Prior Y, Schouder CA, Stapelfeldt H, Cherepanov IN, Lemeshko M, Jäger W, Wu J. Femtosecond Rotational Dynamics of D_{2} Molecules in Superfluid Helium Nanodroplets. PHYSICAL REVIEW LETTERS 2022; 128:243201. [PMID: 35776471 DOI: 10.1103/physrevlett.128.243201] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/07/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Rotational dynamics of D_{2} molecules inside helium nanodroplets is induced by a moderately intense femtosecond pump pulse and measured as a function of time by recording the yield of HeD^{+} ions, created through strong-field dissociative ionization with a delayed femtosecond probe pulse. The yield oscillates with a period of 185 fs, reflecting field-free rotational wave packet dynamics, and the oscillation persists for more than 500 periods. Within the experimental uncertainty, the rotational constant B_{He} of the in-droplet D_{2} molecule, determined by Fourier analysis, is the same as B_{gas} for an isolated D_{2} molecule. Our observations show that the D_{2} molecules inside helium nanodroplets essentially rotate as free D_{2} molecules.
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Affiliation(s)
- Junjie Qiang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Lianrong Zhou
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Peifen Lu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Kang Lin
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Yongzhe Ma
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Shengzhe Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Chenxu Lu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Wenyu Jiang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Fenghao Sun
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Wenbin Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Hui Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Xiaochun Gong
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Ilya Sh Averbukh
- AMOS and Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yehiam Prior
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
- AMOS and Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Constant A Schouder
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Henrik Stapelfeldt
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - Igor N Cherepanov
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Mikhail Lemeshko
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Wolfgang Jäger
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Jian Wu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Shanxi 030006, China
- CAS Center for Excellence in Ultra-intense Laser Science, Shanghai 201800, China
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6
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Beer A, Damari R, Chen Y, Fleischer S. Molecular Orientation-Induced Second-Harmonic Generation: Deciphering Different Contributions Apart. J Phys Chem A 2022; 126:3732-3738. [PMID: 35654048 PMCID: PMC9207934 DOI: 10.1021/acs.jpca.2c03237] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
![]()
We demonstrate and
explore an all-optical technique for direct
monitoring of the orientation dynamics in gas-phase molecular ensembles.
The technique termed “MOISH” utilizes the transiently
lifted inversion symmetry of polar gas media and provides a sensitive
and spatially localized probing of the second-harmonic generation
signal that is directly correlated with the orientation of the gas.
Our experimental results reveal selective electronic and nuclear dynamical
contributions to the overall nonlinear optical signal and decipher
them apart using the “reporter gas” approach. “MOISH”
provides new crucial means for implementing advanced coherent rotational
control via concerted excitation by both terahertz and optical fields.
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Affiliation(s)
- Amit Beer
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel.,Tel-Aviv University Center for Light-Matter-Interaction, Tel Aviv 6997801, Israel
| | - Ran Damari
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel.,Tel-Aviv University Center for Light-Matter-Interaction, Tel Aviv 6997801, Israel
| | - Yun Chen
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Sharly Fleischer
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel.,Tel-Aviv University Center for Light-Matter-Interaction, Tel Aviv 6997801, Israel
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7
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Hartmann JM, Boulet C, Zhang H, Billard F, Faucher O, Lavorel B. Collisional dissipation of the laser-induced alignment of ethane gas: Energy corrected sudden quantum model. J Chem Phys 2018; 149:214305. [PMID: 30525727 DOI: 10.1063/1.5053963] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We present the first quantum mechanical model of the collisional dissipation of the alignment of a gas of symmetric-top molecules (ethane) impulsively induced by a linearly polarized non-resonant laser field. The approach is based on use of the Bloch model and of the Markov and secular approximations in which the effects of collisions are taken into account through the state-to-state rates associated with exchanges among the various rotational states. These rates are constructed using the Energy Corrected Sudden (ECS) approximation with (a few) input parameters obtained independently from fits of the pressure-broadening coefficients of ethane absorption lines. Based on knowledge of the laser pulse characteristics and on these rates, the time-dependent equation driving the evolution of the density matrix during and after the laser pulse is solved and the time dependence of the so-called "alignment factor" is computed. Comparisons with measurements, free of any adjusted parameter, show that the proposed approach leads to good agreement with measurements. The analysis of the ECS state-to-state collisional rates demonstrates that, as in the case of linear molecules, collision-induced changes of the rotational angular momentum orientation are slower than those of its magnitude. This explains why the collisional decay of the permanent component of the alignment is significantly slower than that of the amplitudes of the transient revivals in both experimental and computed results. It is also shown that, since intermolecular forces within C2H6 colliding pairs weakly depend on rotations of the molecules around their C-C bond, the dissipation mechanism of the alignment in pure ethane is close to that involved in linear molecules.
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Affiliation(s)
- J-M Hartmann
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, École polytechnique, Sorbonne Université, École Normale Supérieure, PSL Research University, F-91120 Palaiseau, France
| | - C Boulet
- Institut des Sciences Moléculaires d'Orsay, CNRS, Université Paris-Sud, Université Paris-Saclay, Orsay F-91405, France
| | - H Zhang
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, Université Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - F Billard
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, Université Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - O Faucher
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, Université Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - B Lavorel
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, Université Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
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8
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Hartmann JM, Boulet C, Zhang H, Billard F, Faucher O, Lavorel B. Collisional dissipation of the laser-induced alignment of ethane gas: A requantized classical model. J Chem Phys 2018; 149:154301. [PMID: 30342447 DOI: 10.1063/1.5046899] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present the first theoretical study of collisional dissipation of the alignment of a symmetric-top molecule (ethane gas) impulsively induced by a linearly polarized non-resonant laser field. For this, Classical Molecular Dynamics Simulations (CMDSs) are carried out for an ensemble of C2H6 molecules based on knowledge of the laser-pulse characteristics and on an input intermolecular potential. These provide, for a given gas pressure and initial temperature, the orientations of all molecules at all times from which the alignment factor is directly obtained. Comparisons with measurements show that these CMDSs well predict the permanent alignment induced by the laser pulse and its decay with time but, as expected, fail in generating alignment revivals. However, it is shown that introducing a simple requantization procedure in the CMDS "creates" these revivals and that their predicted dissipation decay agrees very well with measured values. The calculations also confirm that, as for linear molecules, the permanent alignment of ethane decays more slowly than the transient revivals. The influence of the intermolecular potential is studied as well as that of the degree of freedom associated with the molecular rotation around the symmetry axis. This reveals that ethane practically behaves as a linear molecule because the intermolecular potential is only weakly sensitive to rotation around the C-C axis.
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Affiliation(s)
- J-M Hartmann
- Laboratoire de Météorologie Dynamique/IPSL, CNRS, École polytechnique, Sorbonne Université, École Normale Supérieure, PSL Research University, F-91120 Palaiseau, France
| | - C Boulet
- Institut des Sciences Moléculaires d'Orsay, CNRS, Université Paris-Sud, Université Paris-Saclay, Orsay F-91405, France
| | - H Zhang
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - F Billard
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - O Faucher
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - B Lavorel
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
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9
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Thomas EF, Søndergaard AA, Shepperson B, Henriksen NE, Stapelfeldt H. Hyperfine-Structure-Induced Depolarization of Impulsively Aligned I_{2} Molecules. PHYSICAL REVIEW LETTERS 2018; 120:163202. [PMID: 29756917 DOI: 10.1103/physrevlett.120.163202] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Indexed: 06/08/2023]
Abstract
A moderately intense 450 fs laser pulse is used to create rotational wave packets in gas phase I_{2} molecules. The ensuing time-dependent alignment, measured by Coulomb explosion imaging with a delayed probe pulse, exhibits the characteristic revival structures expected for rotational wave packets but also a complex nonperiodic substructure and decreasing mean alignment not observed before. A quantum mechanical model attributes the phenomena to coupling between the rotational angular momenta and the nuclear spins through the electric quadrupole interaction. The calculated alignment trace agrees very well with the experimental results.
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Affiliation(s)
- Esben F Thomas
- Department of Chemistry, Technical University of Denmark, Building 206, DK-2800 Kongens Lyngby, Denmark
| | - Anders A Søndergaard
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Benjamin Shepperson
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Niels E Henriksen
- Department of Chemistry, Technical University of Denmark, Building 206, DK-2800 Kongens Lyngby, Denmark
| | - Henrik Stapelfeldt
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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10
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Zhang H, Billard F, Yu X, Faucher O, Lavorel B. Dissipation dynamics of field-free molecular alignment for symmetric-top molecules: Ethane (C2H6). J Chem Phys 2018; 148:124303. [DOI: 10.1063/1.5019356] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- H. Zhang
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - F. Billard
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - X. Yu
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - O. Faucher
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
| | - B. Lavorel
- Laboratoire Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS-Université, Bourgogne-Franche Comté, 9 Ave. A. Savary, BP 47 870, F-21078 Dijon Cedex, France
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11
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Grohmann T, Seideman T, Leibscher M. Theory of torsional control for G16-type molecules. J Chem Phys 2018. [DOI: 10.1063/1.4997462] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Thomas Grohmann
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd., Evanston, Illinois 60208, USA
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Tamar Seideman
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd., Evanston, Illinois 60208, USA
| | - Monika Leibscher
- Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstr. 2, 30167 Hannover, Germany
- Institut für Physikalische Chemie, Christian-Albrechts-Universität Kiel, Olshausenstr. 40, 24098 Kiel, Germany
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12
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Damari R, Rosenberg D, Fleischer S. Coherent Radiative Decay of Molecular Rotations: A Comparative Study of Terahertz-Oriented versus Optically Aligned Molecular Ensembles. PHYSICAL REVIEW LETTERS 2017; 119:033002. [PMID: 28777613 DOI: 10.1103/physrevlett.119.033002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Indexed: 06/07/2023]
Abstract
The decay of field-free rotational dynamics is experimentally studied by two complementary methods: laser-induced molecular alignment and terahertz-field-induced molecular orientation. A comparison between the decay rates of different molecular species at various gas pressures reveals that oriented molecular ensembles decay faster than aligned ensembles. The discrepancy in decay rates is attributed to the coherent radiation emitted by the transiently oriented ensembles and is absent from aligned molecules. The experimental results reveal the dramatic contribution of coherent radiative emission to the observed decay of rotational dynamics and underline a general phenomenon expected whenever field-free coherent dipole oscillations are induced.
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Affiliation(s)
- Ran Damari
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, 6997801 Israel and Tel-Aviv University center for Light-Matter-Interaction, Tel Aviv, 6997801 Israel
| | - Dina Rosenberg
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, 6997801 Israel and Tel-Aviv University center for Light-Matter-Interaction, Tel Aviv, 6997801 Israel
| | - Sharly Fleischer
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, 6997801 Israel and Tel-Aviv University center for Light-Matter-Interaction, Tel Aviv, 6997801 Israel
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13
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Steinitz U, Khodorkovsky Y, Hartmann J, Averbukh IS. Dynamics and Hydrodynamics of Molecular Superrotors. Chemphyschem 2016; 17:3795-3810. [DOI: 10.1002/cphc.201600508] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Uri Steinitz
- AMOS and Department of Chemical Physics Weizmann Institute of Science 234 Herzl St. Rehovot 76100 Israel
| | - Yuri Khodorkovsky
- AMOS and Department of Chemical Physics Weizmann Institute of Science 234 Herzl St. Rehovot 76100 Israel
| | - Jean‐Michel Hartmann
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS (UMR 7583) Université Paris Est Créteil, Université Paris Diderot, Institut Pierre-Simon Laplace 94010 Créteil Cedex France
| | - Ilya Sh. Averbukh
- AMOS and Department of Chemical Physics Weizmann Institute of Science 234 Herzl St. Rehovot 76100 Israel
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14
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Yachmenev A, Yurchenko SN. Detecting Chirality in Molecules by Linearly Polarized Laser Fields. PHYSICAL REVIEW LETTERS 2016; 117:033001. [PMID: 27472111 DOI: 10.1103/physrevlett.117.033001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Indexed: 06/06/2023]
Abstract
A new scheme for enantiomer differentiation of chiral molecules using a pair of linearly polarized intense ultrashort laser pulses with skewed mutual polarization is presented. The technique relies on the fact that the off-diagonal anisotropic contributions to the electric polarizability tensor for two enantiomers have different signs. Exploiting this property, we are able to excite a coherent unidirectional rotation of two enantiomers with a π phase difference in the molecular electric dipole moment. The approach is robust and suitable for relatively high temperatures of molecular samples, making it applicable for selective chiral analysis of mixtures, and to chiral molecules with low barriers between enantiomers. As an illustration, we present nanosecond laser-driven dynamics of a tetratomic nonrigid chiral molecule with short-lived chirality. The ultrafast time scale of the proposed technique is well suited to study parity violation in molecular systems in short-lived chiral states.
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Affiliation(s)
- Andrey Yachmenev
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Sergei N Yurchenko
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
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15
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Sharma K, Friedrich B. Pair-eigenstates and mutual alignment of coupled molecular rotors in a magnetic field. Phys Chem Chem Phys 2016; 18:13467-77. [PMID: 27126576 DOI: 10.1039/c6cp00390g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We examine the rotational states of a pair of polar (2)Σ molecules subject to a uniform magnetic field. The electric dipole-dipole interaction between the molecules creates entangled pair-eigenstates of two types. In one type, the Zeeman interaction between the inherently paramagnetic molecules and the magnetic field destroys the entanglement of the pair-eigenstates, whereas in the other type it does not. The pair-eigenstates exhibit numerous intersections, which become avoided for pair-eigenstates comprised of individual states that meet the selection rules ΔJi = 0, ± 1, ΔNi = 2n (n = 0, ±1, ±2,…), and ΔMi = 0, ± 1 imposed by the electric dipole-dipole operator. Here Ji, Ni and Mi are the total, rotational and projection angular momentum quantum numbers of molecules i = 1, 2 in the absence of the electric dipole-dipole interaction. We evaluate the mutual alignment of the pair-eigenstates and find it to be independent of the magnetic field, except for states that undergo avoided crossings, in which case the alignment of the interacting states is interchanged at the magnetic field corresponding to the crossing point. We present an analytic model which provides ready estimates of the pairwise alignment cosine that characterises the mutual alignment of the pair of coupled rotors.
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Affiliation(s)
- Ketan Sharma
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
| | - Bretislav Friedrich
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
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16
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Polok K, Gadomski W, Ratajska-Gadomska B. Femtosecond optical Kerr effect setup with signal "live view" for measurements in the solid, liquid, and gas phases. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:103109. [PMID: 26520942 DOI: 10.1063/1.4932531] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present the experimental setup constructed in our laboratory for measurement of the femtosecond optical Kerr effect. The setup allows measurements with high temporal resolution and acquisition speed. The high signal to noise ratio is obtained with use of a homemade balanced detector. Due to the high acquisition speed and good signal to noise ratio, it is possible to have a "live view" of the signal and to easily tune the sample position and orientation before the measurement. We show the example results obtained in the solid, liquid, and the gas phases and we use them in order to check on the precision of our setup. As the samples we have used a YAG crystal, liquid acetone, and atmospheric air. In the latter two cases, a good agreement with the literature data has been found. The measurements in the gas phase confirm that our setup, although utilizing low energy pulses from the sapphire oscillator, is able to acquire high quality rotational signal in a low density sample.
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Affiliation(s)
- K Polok
- Laboratory of Physicochemistry of Dielectrics and Magnetics, Department of Chemistry, University of Warsaw, ul. Żwirki i Wigury 101, 01-089 Warsaw, Poland
| | - W Gadomski
- Laboratory of Physicochemistry of Dielectrics and Magnetics, Department of Chemistry, University of Warsaw, ul. Żwirki i Wigury 101, 01-089 Warsaw, Poland
| | - B Ratajska-Gadomska
- Laboratory of Physicochemistry of Dielectrics and Magnetics, Department of Chemistry, University of Warsaw, ul. Żwirki i Wigury 101, 01-089 Warsaw, Poland
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17
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Khodorkovsky Y, Steinitz U, Hartmann JM, Averbukh IS. Collisional dynamics in a gas of molecular super-rotors. Nat Commun 2015; 6:7791. [PMID: 26160223 PMCID: PMC4510972 DOI: 10.1038/ncomms8791] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 06/10/2015] [Indexed: 11/25/2022] Open
Abstract
Recently, femtosecond laser techniques have been developed that are capable of bringing gas molecules to extremely fast rotation in a very short time, while keeping their translational motion relatively slow. Here we study collisional equilibration dynamics of this new state of molecular gases. We show that the route to equilibrium starts with a metastable 'gyroscopic stage' in the course of which the molecules maintain their fast rotation and orientation of the angular momentum through many collisions. The inhibited rotational-translational relaxation is characterized by a persistent anisotropy in the molecular angular distribution, and is manifested in the optical birefringence and anisotropic diffusion in the gas. After a certain induction time, the 'gyroscopic stage' is abruptly terminated by an explosive rotational-translational energy exchange, leading the gas towards the final equilibrium. We illustrate our conclusions by direct molecular dynamics simulation of several gases of linear molecules.
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Affiliation(s)
- Yuri Khodorkovsky
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Uri Steinitz
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jean-Michel Hartmann
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA) CNRS (UMR 7583), Université Paris Est Créteil, Université Paris Diderot, Institut Pierre-Simon Laplace, 94010 Créteil, France
| | - Ilya Sh. Averbukh
- Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
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18
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Milner AA, Korobenko A, Hepburn JW, Milner V. Effects of ultrafast molecular rotation on collisional decoherence. PHYSICAL REVIEW LETTERS 2014; 113:043005. [PMID: 25105617 DOI: 10.1103/physrevlett.113.043005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Indexed: 06/03/2023]
Abstract
Using an optical centrifuge to control molecular rotation in an extremely broad range of angular momenta, we study coherent rotational dynamics of nitrogen molecules in the presence of collisions. We cover the range of rotational quantum numbers between J=8 and J=66 at room temperature and study a crossover between the adiabatic and nonadiabatic regimes of rotational relaxation, which cannot be easily accessed by thermal means. We demonstrate that the rate of rotational decoherence changes by more than an order of magnitude in this range of J values and show that its dependence on J can be described by a simplified scaling law.
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Affiliation(s)
- Alexander A Milner
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, Canada V6T 1Z1
| | - Aleksey Korobenko
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, Canada V6T 1Z1
| | - John W Hepburn
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, Canada V6T 1Z1
| | - Valery Milner
- Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, Canada V6T 1Z1
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19
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Schmidt B, Friedrich B. Topology of surfaces for molecular Stark energy, alignment, and orientation generated by combined permanent and induced electric dipole interactions. J Chem Phys 2014; 140:064317. [DOI: 10.1063/1.4864465] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Affiliation(s)
- Mikhail Lemeshko
- a ITAMP, Harvard-Smithsonian Center for Astrophysics , Cambridge , MA , 02138 , USA
- b Physics Department , Harvard University , Cambridge , MA , 02138 , USA
- c Kavli Institute for Theoretical Physics , University of California , Santa Barbara , CA , 93106 , USA
| | - Roman V. Krems
- c Kavli Institute for Theoretical Physics , University of California , Santa Barbara , CA , 93106 , USA
- d Department of Chemistry , University of British Columbia , BC V6T 1Z1, Vancouver , Canada
| | - John M. Doyle
- b Physics Department , Harvard University , Cambridge , MA , 02138 , USA
| | - Sabre Kais
- e Departments of Chemistry and Physics , Purdue University , West Lafayette , IN , 47907 , USA
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21
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Pentlehner D, Nielsen JH, Slenczka A, Mølmer K, Stapelfeldt H. Impulsive laser induced alignment of molecules dissolved in helium nanodroplets. PHYSICAL REVIEW LETTERS 2013; 110:093002. [PMID: 23496707 DOI: 10.1103/physrevlett.110.093002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Indexed: 06/01/2023]
Abstract
We show that a 450 fs nonresonant, moderately intense, linearly polarized laser pulse can induce field-free molecular axis alignment of methyliodide (CH(3)I) molecules dissolved in a helium nanodroplet. Time-resolved measurements reveal rotational dynamics much slower than that of isolated molecules and absence of the sharp transient alignment recurrences characteristic of gas phase molecules. Our results presage a range of new opportunities for exploring both molecular dynamics in a dissipative environment and the properties of He nanodroplets.
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22
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Königsmann F, Schwentner N, Anderson DT. Time resolved dynamics of phonons and rotons in solid parahydrogen. Phys Chem Chem Phys 2013; 15:17435-51. [DOI: 10.1039/c3cp52055b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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23
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Fleischer S, Field RW, Nelson KA. Commensurate two-quantum coherences induced by time-delayed THz fields. PHYSICAL REVIEW LETTERS 2012; 109:123603. [PMID: 23005948 DOI: 10.1103/physrevlett.109.123603] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Indexed: 06/01/2023]
Abstract
The interaction of carbonyl sulfide dipolar gas molecules with two time-delayed, single-cycle THz pulses is shown both experimentally and theoretically to induce two-quantum rotational coherences that are significantly enhanced with respect to those induced by one THz pulse, depending on the relative delay of the pulses. The underlying phenomenon is quite general in that it can occur even after a single THz pulse if more than one molecular species is present, since the free induction decay emitted by one species (demonstrated here by atmospheric water vapor) can provide the second field interaction for the other.
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Affiliation(s)
- Sharly Fleischer
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, 02139, USA
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24
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Hartmann JM, Boulet C. Quantum and classical approaches for rotational relaxation and nonresonant laser alignment of linear molecules: A comparison for CO2 gas in the nonadiabatic regime. J Chem Phys 2012; 136:184302. [DOI: 10.1063/1.4705264] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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25
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Lindgren J, Hulkko E, Pettersson M, Kiljunen T. Rotational coherence imaging and control for CN molecules through time-frequency resolved coherent anti-Stokes Raman scattering. J Chem Phys 2011; 135:224514. [PMID: 22168710 DOI: 10.1063/1.3665934] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Numerical wave packet simulations are performed for studying coherent anti-Stokes Raman scattering (CARS) for CN radicals. Electronic coherence is created by femtosecond laser pulses between the X(2)Σ and B(2)Σ states. Due to the large energy separation of vibrational states, the wave packets are superpositions of rotational states only. This allows for a specially detailed inspection of the second- and third-order coherences by a two-dimensional imaging approach. We present the time-frequency domain images to illustrate the intra- and intermolecular interferences, and discuss the procedure to rationally control and experimentally detect the interferograms in solid Xe environment.
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Affiliation(s)
- Johan Lindgren
- Department of Chemistry, Nanoscience Center, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
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26
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Owschimikow N, Schmidt B, Schwentner N. Laser-induced alignment and anti-alignment of rotationally excited molecules. Phys Chem Chem Phys 2011; 13:8671-80. [PMID: 21290046 DOI: 10.1039/c0cp02260h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We numerically investigate the post-pulse alignment of rotationally excited diatomic molecules upon nonresonant interaction with a linearly polarized laser pulse. In addition to the simulations, we develop a simple model which qualitatively describes the shape and amplitude of post-pulse alignment induced by a laser pulse of moderate power density. In our treatment we take into account that molecules in rotationally excited states can interact with a laser pulse not only by absorbing energy but also by stimulated emission. The extent to which these processes are present in the interaction depends, on the one hand, on the directionality of the molecular angular momentum (given by the M quantum number), and on the other hand on the ratio of transition frequencies and pulse duration (determined by the J number). A rotational wave packet created by a strong pulse from an initially pure state contains a broad range of rotational levels, over which the character of the interaction can change from non-adiabatic to adiabatic. Depending on the laser pulse duration and amplitude, the transition from the non-adiabatic to the adiabatic limit proceeds through a region with dominant rotational heating, or alignment, for short pulses and a large region with rotational cooling, and correspondingly preferred anti-alignment, for longer pulses.
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Affiliation(s)
- Nina Owschimikow
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.
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