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Porer M, Fechner M, Bothschafter EM, Rettig L, Savoini M, Esposito V, Rittmann J, Kubli M, Neugebauer MJ, Abreu E, Kubacka T, Huber T, Lantz G, Parchenko S, Grübel S, Paarmann A, Noack J, Beaud P, Ingold G, Aschauer U, Johnson SL, Staub U. Ultrafast Relaxation Dynamics of the Antiferrodistortive Phase in Ca Doped SrTiO_{3}. Phys Rev Lett 2018; 121:055701. [PMID: 30118273 DOI: 10.1103/physrevlett.121.055701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Indexed: 06/08/2023]
Abstract
The ultrafast dynamics of the octahedral rotation in Ca:SrTiO_{3} is studied by time-resolved x-ray diffraction after photoexcitation over the band gap. By monitoring the diffraction intensity of a superlattice reflection that is directly related to the structural order parameter of the soft-mode driven antiferrodistortive phase in Ca:SrTiO_{3}, we observe an ultrafast relaxation on a 0.2 ps timescale of the rotation of the oxygen octahedron, which is found to be independent of the initial temperature despite large changes in the corresponding soft-mode frequency. A further, much smaller reduction on a slower picosecond timescale is attributed to thermal effects. Time-dependent density-functional-theory calculations show that the fast response can be ascribed to an ultrafast displacive modification of the soft-mode potential towards the normal state induced by holes created in the oxygen 2p states.
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Affiliation(s)
- M Porer
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - M Fechner
- Max Planck Institute for the Structure and Dynamics of Matter, CFEL, 22761 Hamburg, Germany
- Materials Theory, ETH Zürich, 8093 Zürich, Switzerland
| | - E M Bothschafter
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - L Rettig
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - M Savoini
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - V Esposito
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - J Rittmann
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - M Kubli
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - M J Neugebauer
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - E Abreu
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - T Kubacka
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - T Huber
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - G Lantz
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - S Parchenko
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - S Grübel
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - A Paarmann
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - J Noack
- Department of Inorganic Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - P Beaud
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - G Ingold
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - U Aschauer
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - S L Johnson
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - U Staub
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
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Bothschafter E, Paarmann A, Karpowicz N, Zijlstra E, Garcia M, Krausz F, Kienberger R, Ernstorfer R. Interband excitation and carrier relaxation as displacive driving force for coherent phonons. EPJ Web of Conferences 2013. [DOI: 10.1051/epjconf/20134104021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Paarmann A, Hayashi T, Mukamel S, Miller RJD. Nonlinear response of vibrational excitons: simulating the two-dimensional infrared spectrum of liquid water. J Chem Phys 2009; 130:204110. [PMID: 19485440 PMCID: PMC2719475 DOI: 10.1063/1.3139003] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 04/28/2009] [Indexed: 11/15/2022] Open
Abstract
A simulation formalism for the nonlinear response of vibrational excitons is presented and applied to the OH stretching vibrations of neat liquid H(2)O. The method employs numerical integration of the Schrodinger equation and allows explicit treatment of fluctuating transition frequencies, vibrational couplings, dipole moments, and the anharmonicities of all these quantities, as well as nonadiabatic effects. The split operator technique greatly increases computational feasibility and performance. The electrostatic map for the OH stretching vibrations in liquid water employed in our previous study [A. Paarmann et al., J. Chem. Phys. 128, 191103 (2008)] is presented. The two-dimensional spectra are in close agreement with experiment. The fast 100 fs dynamics are primarily attributed to intramolecular mixing between states in the two-dimensional OH stretching potential. Small intermolecular couplings are sufficient to reproduce the experimental energy transfer time scales. Interference effects between Liouville pathways in excitonic systems and their impact on the analysis of the nonlinear response are discussed.
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Affiliation(s)
- A Paarmann
- Department of Physics and Institute for Optical Sciences, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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Paarmann A, Hayashi T, Mukamel S, Miller RJD. Probing intermolecular couplings in liquid water with two-dimensional infrared photon echo spectroscopy. J Chem Phys 2008; 128:191103. [PMID: 18500848 DOI: 10.1063/1.2919050] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Two-dimensional infrared photon echo and pump probe studies of the OH stretch vibration provide a sensitive probe of the correlations and couplings in the hydrogen bond network of liquid water. The nonlinear response is simulated using numerical integration of the Schrodinger equation with a Hamiltonian constructed to explicitly treat intermolecular coupling and nonadiabatic effects in the highly disordered singly and doubly excited vibrational exciton manifolds. The simulated two-dimensional spectra are in close agreement with our recent experimental results. The high sensitivity of the OH stretch vibration to the bath dynamics is found to arise from intramolecular mixing between states in the two-dimensional anharmonic OH stretch potential. Surprisingly small intermolecular couplings reproduce the experimentally observed intermolecular energy transfer times.
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Affiliation(s)
- A Paarmann
- Institute for Optical Sciences and Departments of Physics and Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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Kraemer D, Cowan ML, Paarmann A, Huse N, Nibbering ETJ, Elsaesser T, Miller RJD. Temperature dependence of the two-dimensional infrared spectrum of liquid H2O. Proc Natl Acad Sci U S A 2008; 105:437-42. [PMID: 18182497 PMCID: PMC2206554 DOI: 10.1073/pnas.0705792105] [Citation(s) in RCA: 230] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Indexed: 11/18/2022] Open
Abstract
Two-dimensional infrared photon-echo measurements of the OH stretching vibration in liquid H2O are performed at various temperatures. Spectral diffusion and resonant energy transfer occur on a time scale much shorter than the average hydrogen bond lifetime of approximately 1 ps. Room temperature measurements show a loss of frequency and, thus, structural correlations on a 50-fs time scale. Weakly hydrogen-bonded OH stretching oscillators absorbing at high frequencies undergo slower spectral diffusion than strongly bonded oscillators. In the temperature range from 340 to 274 K, the loss in memory slows down with decreasing temperature. At 274 K, frequency correlations in the OH stretch vibration persist beyond approximately 200 fs, pointing to a reduction in dephasing by librational excitations. Polarization-resolved pump-probe studies give a resonant intermolecular energy transfer time of 80 fs, which is unaffected by temperature. At low temperature, structural correlations persist longer than the energy transfer time, suggesting a delocalization of OH stretching excitations over several water molecules.
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Affiliation(s)
- D. Kraemer
- *Institute for Optical Sciences, Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S3H6; and
| | - M. L. Cowan
- *Institute for Optical Sciences, Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S3H6; and
| | - A. Paarmann
- *Institute for Optical Sciences, Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S3H6; and
| | - N. Huse
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - E. T. J. Nibbering
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - T. Elsaesser
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin, Germany
| | - R. J. Dwayne Miller
- *Institute for Optical Sciences, Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON, Canada M5S3H6; and
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