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

Journal of Modern Optics

Two-photon excited coherence gratings in inhomogeneously broadened organic solid

Alex Karotki, Mikalai M. Kruk, Mikhail A. Drobizhev, Alexander Rebane

Published Mar 1, 2002• 13 citations
Publisher

Abstract

For the first time a frequency-domain grating is observed in the visible region as a result of coherence excited by two-photon absorption of time-delayed near-IR femtosecond pulses in an inhomogeneously broadened organic solid-state system. The grating appears in chlorin (2,3-dihydroporphyrin)-doped polymer film at low temperature and is detected in two different ways. First, modulation is observed in the pure electronic fluorescence band upon 'resonant' two-photon excitation with laser carrier frequency equal to one-half of the fluorescence band maximum. Second, upon long exposure time at half of the transition frequency, a persistent spectral hole with periodic structure is observed. The two-photon absorption spectrum of the chlorin molecule in the spectral range 1130–1310nm is also presented for the first time.

DOI
10.1080/09500340110088605

Related papers

Phonon-induced phase shift of spectral gratings created upon two-photon excitation in inhomogeneously broadened organic system

Mikhail A. Drobizhev, Alex Karotki, Alexander Rebane

Summary from only given. We have shown recently that spectral gratings can be created upon simultaneous two-photon absorption (TPA) from a pair of femtosecond pulses. In this paper we study, for the first time to our knowledge, the dependence of the frequency-domain grating on the shape of homogeneous absorption spectrum of two-photon transition. We take advantage of the complete absence of Rayleigh scattering at twice the excitation frequency, which allows us to measure resonance fluorescence spectrum as a function of temperature.

Conference on Lasers and Electro-Optics•Jun 25, 2003•1 citation

Femtosecond photon echo in a dye-doped polymer film and the possibility of coherent optical cooling

Vladimir S. Lobkov, S. V. Petrushkin, К. М. Салихов +3 more

The signals of primary and stimulated femtosecond photon echoes are investigated in a dye-doped polymer film at room temperature. The homogeneous S 0 → S 1 spectral line width, which is due to the interaction between the impurity molecules and the quasi-local low-frequency modes, is estimated (≈5 × 1012 Hz). Special attention is paid to the study of spectra of femtosecond echo signals. The short-wave shifts of these spectra, with respect to the spectrum of femtosecond exciting pulses, are observed. These shifts indicate that the anti-Stokes regime of femtosecond pulse emission is realized. Therefore, the coherent regime of laser cooling of solids appears to be possible. The prospects of using of this new cooling regime in the function of a solid-state optical refrigerator are discussed.

Laser Physics•May 1, 2007•8 citations

Coherence from fluorescence correlations: Oscillatory femtosecond fluorescence in pentacene/p-terphenyl

Andreas Tortschanoff, Klemens Brunner, Ch. Warmuth +1 more

Spontaneous fluorescence has been used to measure the coherent femtosecond response of the organic, binary crystal pentacene/p-terphenyl. By using two-pulse excitation with phase-randomized pulses in an interferometric setup and analyzing the variance of the fluctuating intensity of correlated fluorescence photons, femtosecond beatings have been observed. The pattern of these terahertz oscillations is strongly dependent on the detuning frequency range of the exciting pulses, but is rather invariant with regard to the spectral position of the fluorescence probe window. In the interferometric regime of freely propagating pulses novel, ultrafast fluorescence carrier-wave oscillations superimposed to the beat structure have been obtained. The oscillatory signals evolve from a coherent superposition of optical free induction decays, caused by the different electronic transition energies of the pentacene absorber sites O1, O2, O3, and O4, respectively, are monitored as intrinsic, heterodyne beats by the fluorescence square detector. The major part of oscillations is thus considered to result from typical polarization interferences, but vibrational quantum beats are also extractable from the interferogram in the ultimate frequency regime of the pentacene S0→S1ν=1, S0→S1ν=2 resonances. The early picosecond-decay of the fluorescence beats reveals the mechanism of the loss of coherence to be mainly controlled by inhomogeneous dephasing at low phonon temperatures. A model of uncoupled two-level systems that includes Gaussian inhomogeneous broadening of the individual absorber sites and a Gaussian frequency distribution for the excitation pulses can account for the experimental data, quite adequately.

The Journal of Chemical Physics•Mar 1, 1999•19 citations

New coherent transient technique for femtosecond single-shot homogeneous spectrum measurement

Olavi Ollikainen, Jürgen Gallus, Urs P. Wild +1 more

Summary form only given. Coherent optical transients such as photon echo are a versatile method far measurement of the homogeneous absorption spectrum of molecular systems in the presence of strong inhomogeneous broadening. Such experiments require measurement of the decay of the optical coherence, typically accomplished by gradually varying the time delay between the excitation pulses. Time-domain information is then Fourier transformed to frequency domain by a computer. In this paper we demonstrate a new method that yields the homogeneous spectrum in a single shot of femtosecond laser pulse illumination by performing Fourier transformation of coherent optical transient signal with a lens. We apply this method to measure the homogeneous spectrum of dye molecules in a polymer film in a broad range of temperatures.

Conference on Lasers and Electro-Optics•Nov 27, 2002•0 citations

Stimulated femtosecond photon echo in a dye-doped polymer film at room temperature

Vladimir S. Lobkov, A V Leontiev, К. М. Салихов +3 more

It is reported about the first observation (in a solid-state sample) and detailed investigation of the stimulated femtosecond photon echo (SFPE) signals at room temperature in a polyvinylbutural film doped with molecules of phthalocyanine of HW 1009 type at the wavelength of 788 nm. A dependence of relative intensity of these echo-signals on time intervals between the second and the third exciting pulses was studied and the SFPE spectrum was investigated with respect to the spectra of both exciting pulses and signals of self-diffraction. It was found that the linear electron-phonon coupling is weak and the influence of the phonon-side band of the absorption line on the SFPE signals is less significantly than on the signals of primary photon echo.

Laser Physics Letters•Jun 23, 2006•9 citations

Femtosecond photon echo in dye-doped polymer film at liquid nitrogen and room temperatures

Vladimir S. Lobkov, К. М. Салихов, В. В. Самарцев +2 more

The first observation is reported of the primary and stimulated femtosecond photon echoes at liquid nitrogen and room temperatures in a dye-doped polymer film at a wavelength of 780 nm. Echo signals were generated by pulses with the duration of 130 fs. The primary echo signal decay at a liquid nitrogen temperature can not be described by a simple exponential function. There is a fast decay region below 250-300 fs and a slow decay region at longer time intervals. The decay of primary echo signal at room temperature demonstrates complex behavior caused by the presence of the phonon-side band in the optical band of impurity centers. There were also detected signals of the self-diffraction of exciting pulses on a nonequilibrium population difference grating, induced in resonant medium by these pulses.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 3, 2006•2 citations
For the first time a frequency-domain grating is observed in the visible region as a result of coherence excited by two-photon absorption of time-delayed near-IR femtosecond pulses in an inhomogeneously broadened organic solid-state system. The grating appears in chlorin (2,3-dihydroporphyrin)-doped polymer film at low temperature and is detected in two different ways. First, modulation is observed in the pure electronic fluorescence band upon 'resonant' two-photon excitation with laser carrier frequency equal to one-half of the fluorescence band maximum. Second, upon long exposure time at half of the transition frequency, a persistent spectral hole with periodic structure is observed. The two-photon absorption spectrum of the chlorin molecule in the spectral range 1130–1310nm is also presented for the first time.
Summary from only given. We have shown recently that spectral gratings can be created upon simultaneous two-photon absorption (TPA) from a pair of femtosecond pulses. In this paper we study, for the first time to our knowledge, the dependence of the frequency-domain grating on the shape of homogeneous absorption spectrum of two-photon transition. We take advantage of the complete absence of Rayleigh scattering at twice the excitation frequency, which allows us to measure resonance fluorescence spectrum as a function of temperature.
The signals of primary and stimulated femtosecond photon echoes are investigated in a dye-doped polymer film at room temperature. The homogeneous S 0 → S 1 spectral line width, which is due to the interaction between the impurity molecules and the quasi-local low-frequency modes, is estimated (≈5 × 1012 Hz). Special attention is paid to the study of spectra of femtosecond echo signals. The short-wave shifts of these spectra, with respect to the spectrum of femtosecond exciting pulses, are observed. These shifts indicate that the anti-Stokes regime of femtosecond pulse emission is realized. Therefore, the coherent regime of laser cooling of solids appears to be possible. The prospects of using of this new cooling regime in the function of a solid-state optical refrigerator are discussed.
Spontaneous fluorescence has been used to measure the coherent femtosecond response of the organic, binary crystal pentacene/p-terphenyl. By using two-pulse excitation with phase-randomized pulses in an interferometric setup and analyzing the variance of the fluctuating intensity of correlated fluorescence photons, femtosecond beatings have been observed. The pattern of these terahertz oscillations is strongly dependent on the detuning frequency range of the exciting pulses, but is rather invariant with regard to the spectral position of the fluorescence probe window. In the interferometric regime of freely propagating pulses novel, ultrafast fluorescence carrier-wave oscillations superimposed to the beat structure have been obtained. The oscillatory signals evolve from a coherent superposition of optical free induction decays, caused by the different electronic transition energies of the pentacene absorber sites O1, O2, O3, and O4, respectively, are monitored as intrinsic, heterodyne beats by the fluorescence square detector. The major part of oscillations is thus considered to result from typical polarization interferences, but vibrational quantum beats are also extractable from the interferogram in the ultimate frequency regime of the pentacene S0→S1ν=1, S0→S1ν=2 resonances. The early picosecond-decay of the fluorescence beats reveals the mechanism of the loss of coherence to be mainly controlled by inhomogeneous dephasing at low phonon temperatures. A model of uncoupled two-level systems that includes Gaussian inhomogeneous broadening of the individual absorber sites and a Gaussian frequency distribution for the excitation pulses can account for the experimental data, quite adequately.
Summary form only given. Coherent optical transients such as photon echo are a versatile method far measurement of the homogeneous absorption spectrum of molecular systems in the presence of strong inhomogeneous broadening. Such experiments require measurement of the decay of the optical coherence, typically accomplished by gradually varying the time delay between the excitation pulses. Time-domain information is then Fourier transformed to frequency domain by a computer. In this paper we demonstrate a new method that yields the homogeneous spectrum in a single shot of femtosecond laser pulse illumination by performing Fourier transformation of coherent optical transient signal with a lens. We apply this method to measure the homogeneous spectrum of dye molecules in a polymer film in a broad range of temperatures.
It is reported about the first observation (in a solid-state sample) and detailed investigation of the stimulated femtosecond photon echo (SFPE) signals at room temperature in a polyvinylbutural film doped with molecules of phthalocyanine of HW 1009 type at the wavelength of 788 nm. A dependence of relative intensity of these echo-signals on time intervals between the second and the third exciting pulses was studied and the SFPE spectrum was investigated with respect to the spectra of both exciting pulses and signals of self-diffraction. It was found that the linear electron-phonon coupling is weak and the influence of the phonon-side band of the absorption line on the SFPE signals is less significantly than on the signals of primary photon echo.
The first observation is reported of the primary and stimulated femtosecond photon echoes at liquid nitrogen and room temperatures in a dye-doped polymer film at a wavelength of 780 nm. Echo signals were generated by pulses with the duration of 130 fs. The primary echo signal decay at a liquid nitrogen temperature can not be described by a simple exponential function. There is a fast decay region below 250-300 fs and a slow decay region at longer time intervals. The decay of primary echo signal at room temperature demonstrates complex behavior caused by the presence of the phonon-side band in the optical band of impurity centers. There were also detected signals of the self-diffraction of exciting pulses on a nonequilibrium population difference grating, induced in resonant medium by these pulses.