Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

Observation of high-frequency coherent vibrations with strongly chirped probe pulses

Dario Polli, Brida Daniele, Guglielmo Lanzani, Giulio Cerullo

Published Jun 1, 2009• 0 citations
Publisher

Abstract

It is nowadays possible to generate, in different spectral ranges, ultrabroadband light pulses with transform-limited (TL) duration corresponding to a few optical cycles. Whenever broadband pulses are employed, the dispersion experienced by the pulses causes a frequency chirp which may severely lengthen their duration and influence time-resolved measurements. While it is well known that the relative weight of ground-state versus excited-state oscillations can be controlled by the chirp in the pump pulse, the effects of probe pulse chirp have not been fully investigated. In this paper we show, both theoretically and experimentally, that a pump-probe experiment using strongly-chirped probe pulses can preserve the temporal resolution of the TL pulses.

DOI
10.1109/cleoe-eqec.2009.5196377

Related papers

Noisy Optical Pulses Enhance the Temporal Resolution of Pump-Probe Spectroscopy

Kristina Meyer, Christian Ott, Philipp Raith +7 more

Time-resolved measurements of quantum dynamics are based on the availability of controlled events that are shorter than the typical evolution time scale of the processes to be observed. Here we introduce the concept of noise-enhanced pump-probe spectroscopy, allowing the measurement of dynamics significantly shorter than the average pulse duration by exploiting randomly varying, partially coherent light fields consisting of bunched colored noise. These fields are shown to be superior by more than a factor of 10 to frequency-stabilized fields, with important implications for time-resolved experiments at x-ray free-electron lasers and, in general, for measurements at the frontiers of temporal resolution (e.g., attosecond spectroscopy). As an example application, the concept is used to explain the recent experimental observation of vibrational wave-packet motion in D(2)(+) on time scales shorter than the average pulse duration.

arXiv:1110.5536•Physical Review Letters•Mar 1, 2012•94 citations

Weakly chirped pulses in frequency resolved coherent spectroscopy

Niklas Christensson, Yuri Avlasevich, Arkady P. Yartsev +3 more

The role of weakly chirped pulses (time bandwidth product, DeltanuDeltatau<0.61) on three-pulse photon echo signals has been systematically studied. Pulses with varying chirp were characterized with frequency resolved optical gating (FROG) and used to measure spectrally resolved three-pulse photon echoes of a dye in solution. The weakly chirped pulses give rise to markedly different echo signals for population times below approximately 100 fs. The chirped pulses can decrease or enhance spectral signatures of an excited state absorption transition in the echo signal. Furthermore, the observed dephasing dynamics depend on the phase of the electric fields. Simulations based on a three-level model and the electric fields retrieved from the FROG traces give a good agreement for photon echo experiments with both transform limited and chirped pulses. The simulations also allow for a numerical investigation of effects of chirp in two-dimensional spectroscopy. For a two-level system, the chirped pulses result in nonelliptical two-dimensional spectra that can erroneously be interpreted as spectral heterogeneity with frequency dependent dephasing dynamics. Furthermore, chirped pulses can give rise to "false" cross peaks when strong vibrational modes are involved in the system-bath interaction.

The Journal of Chemical Physics•May 7, 2010•16 citations

Frequency-time and time-space mappings with broadband and supercontinuum chirped pulses in coherent wave mixing and pump-probe

Lomonosov Moscow

Broadband and supercontinuum pulses with a lin- ear chirp define a linear transform, mapping the difference between the instantaneous frequencies of pump pulses onto the delay time between these pulses. This delay between the pump pulses can be then mapped onto the spatial coordinate with the use of a broad-beam wave-mixing or pump-probe geometry. The new possibilities offered by these mappings for four-wave-mixing techniques are discussed. The spectral and temporal resolution of chirped-pulse wave-mixing and pump- probe techniques are examined. Single-shot multidimensional wave-mixing techniques using broadband and supercontinuum chirped pulses are discussed.

•Jan 1, 2003•0 citations

Application of chirped ultrashort pulses for generating large-amplitude ground-state vibrational coherence: a computer simulation

Sanford Ruhman, Ronnie Kosloff

Computer simulations are presented to show that frequency-chirped ultrashort pulses, when properly employed, may be more effective than their compressed analogs for generating large-amplitude vibrational coherence in molecular systems. A one-dimensional model, which was used previously to simulate impulsive optical excitation of CsI, is used [ Chem. Phys. Lett.158, 238 ( 1988)]. A negatively chirped pulse (for which the light is red-shifted with time) is devised to excite the population initially onto the excited surface. As this population propagates in the repulsive upper state, the later red-shifted portions of the pulse follow the change in the resonance conditions and effectively dump the population back down into excited vibrational states of the ground surface. These results are compared with the dynamics simulated with the compressed and positively chirped analogs, and the experimental realization of this scheme is discussed.

Journal of the Optical Society of America B•Aug 1, 1990•114 citations

Chirping the probe pulse in a coherent transients experiment

S. J. Weber, B. Girard, B. Chatel

Coherent transients occur when a chirped pump pulse excites a two-level transition. They have been observed with an ultrashort probe pulse. Several studies have been dedicated to using various pump shapes. In this study, the roles of the pump and the probe pulses are reversed. With a Fourier-transform-limited pump pulse followed by a chirped-probe pulse, similar effects can be observed. Finally, the case of two pulses with opposite chirps is considered.

Physical Review A•Feb 18, 2010•1 citation

Stimulated Emission Enhancement Using Shaped Pulses

Arkaprabha Konar, Vadim V. Lozovoy, Marcos M. Dantus

Controlling stimulated emission is of importance because it competes with absorption and fluorescence under intense laser excitation. We performed resonant nonlinear optical spectroscopy measurements using femtosecond pulses shaped by π- or π/2-step phase functions and carried out calculations based on density matrix representation to elucidate the experimental results. In addition, we compared enhancements obtained when using other pulse shaping functions (chirp, third-order dispersion, and a time-delayed probe). The light transmitted through the high optical density solution was dominated by an intense stimulated emission feature that was 14 times greater for shaped pulses than for transform limited pulses. Coherent enhancement depending on the frequency, temporal, and phase characteristics of the shaped pulse is responsible for the experimental observations.

The Journal of Physical Chemistry A•Mar 9, 2016•10 citations
It is nowadays possible to generate, in different spectral ranges, ultrabroadband light pulses with transform-limited (TL) duration corresponding to a few optical cycles. Whenever broadband pulses are employed, the dispersion experienced by the pulses causes a frequency chirp which may severely lengthen their duration and influence time-resolved measurements. While it is well known that the relative weight of ground-state versus excited-state oscillations can be controlled by the chirp in the pump pulse, the effects of probe pulse chirp have not been fully investigated. In this paper we show, both theoretically and experimentally, that a pump-probe experiment using strongly-chirped probe pulses can preserve the temporal resolution of the TL pulses.
Time-resolved measurements of quantum dynamics are based on the availability of controlled events that are shorter than the typical evolution time scale of the processes to be observed. Here we introduce the concept of noise-enhanced pump-probe spectroscopy, allowing the measurement of dynamics significantly shorter than the average pulse duration by exploiting randomly varying, partially coherent light fields consisting of bunched colored noise. These fields are shown to be superior by more than a factor of 10 to frequency-stabilized fields, with important implications for time-resolved experiments at x-ray free-electron lasers and, in general, for measurements at the frontiers of temporal resolution (e.g., attosecond spectroscopy). As an example application, the concept is used to explain the recent experimental observation of vibrational wave-packet motion in D(2)(+) on time scales shorter than the average pulse duration.
The role of weakly chirped pulses (time bandwidth product, DeltanuDeltatau<0.61) on three-pulse photon echo signals has been systematically studied. Pulses with varying chirp were characterized with frequency resolved optical gating (FROG) and used to measure spectrally resolved three-pulse photon echoes of a dye in solution. The weakly chirped pulses give rise to markedly different echo signals for population times below approximately 100 fs. The chirped pulses can decrease or enhance spectral signatures of an excited state absorption transition in the echo signal. Furthermore, the observed dephasing dynamics depend on the phase of the electric fields. Simulations based on a three-level model and the electric fields retrieved from the FROG traces give a good agreement for photon echo experiments with both transform limited and chirped pulses. The simulations also allow for a numerical investigation of effects of chirp in two-dimensional spectroscopy. For a two-level system, the chirped pulses result in nonelliptical two-dimensional spectra that can erroneously be interpreted as spectral heterogeneity with frequency dependent dephasing dynamics. Furthermore, chirped pulses can give rise to "false" cross peaks when strong vibrational modes are involved in the system-bath interaction.
Broadband and supercontinuum pulses with a lin- ear chirp define a linear transform, mapping the difference between the instantaneous frequencies of pump pulses onto the delay time between these pulses. This delay between the pump pulses can be then mapped onto the spatial coordinate with the use of a broad-beam wave-mixing or pump-probe geometry. The new possibilities offered by these mappings for four-wave-mixing techniques are discussed. The spectral and temporal resolution of chirped-pulse wave-mixing and pump- probe techniques are examined. Single-shot multidimensional wave-mixing techniques using broadband and supercontinuum chirped pulses are discussed.
Computer simulations are presented to show that frequency-chirped ultrashort pulses, when properly employed, may be more effective than their compressed analogs for generating large-amplitude vibrational coherence in molecular systems. A one-dimensional model, which was used previously to simulate impulsive optical excitation of CsI, is used [ Chem. Phys. Lett.158, 238 ( 1988)]. A negatively chirped pulse (for which the light is red-shifted with time) is devised to excite the population initially onto the excited surface. As this population propagates in the repulsive upper state, the later red-shifted portions of the pulse follow the change in the resonance conditions and effectively dump the population back down into excited vibrational states of the ground surface. These results are compared with the dynamics simulated with the compressed and positively chirped analogs, and the experimental realization of this scheme is discussed.
Controlling stimulated emission is of importance because it competes with absorption and fluorescence under intense laser excitation. We performed resonant nonlinear optical spectroscopy measurements using femtosecond pulses shaped by π- or π/2-step phase functions and carried out calculations based on density matrix representation to elucidate the experimental results. In addition, we compared enhancements obtained when using other pulse shaping functions (chirp, third-order dispersion, and a time-delayed probe). The light transmitted through the high optical density solution was dominated by an intense stimulated emission feature that was 14 times greater for shaped pulses than for transform limited pulses. Coherent enhancement depending on the frequency, temporal, and phase characteristics of the shaped pulse is responsible for the experimental observations.