Femtosecond Pump−Probe Studies of Dichlorine Monoxide in Solution

AbstractOptical pump-probe measurements were performed on planar slab waveguides containing silicon nanocrystals in an attempt to measure optical gain from photo-excited silicon nanocrystals. Two experiments were performed, one with a continuous-wave probe beam and a pulsed pump beam, giving a time resolution of approximately 25 ns, and the other with a pulsed pump and probe beam, giving a time resolution of approximately 10 ps. In both cases the intensity of the probe beam was found to be attenuated by the pump beam, with the attenuation increasing monotonically with increasing pump power. Time-resolved measurements using the first experimental arrangement showed that the probe signal recovered its initial intensity on a time scale of 45-70 μs, a value comparable to the exciton lifetime in Si nanocrystals. These data are shown to be consistent with an induced absorption process such as confined carrier absorption. No evidence for optical gain was observed.

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Density matrix and rate equation analyses for picosecond pump/probe combustion diagnostics

AIAA Journal ◽

10.2514/3.14233 ◽

1999 ◽

Vol 37 ◽

pp. 723-731

Author(s):

Thomas Settersten ◽

Mark Linne ◽

James Gord ◽

Gregory Feichtner

Keyword(s):

Density Matrix ◽

Rate Equation ◽

Pump Probe ◽

Combustion Diagnostics

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Two-Dimensional Infrared Spectroscopy From the Gas to Liquid Phase: Density Dependent J-Scrambling, Vibrational Relaxation, and the Onset of Liquid Character

10.26434/chemrxiv.9700427 ◽

2019 ◽

Author(s):

Greg Ng Pack ◽

Matthew Rotondaro ◽

Parth Shah ◽

Aritra Mandal ◽

Shyamsunder Erramilli ◽

...

Keyword(s):

Vibrational Energy ◽

Rotational Relaxation ◽

Vibrational Energy Relaxation ◽

Pump Probe ◽

Solution Dynamics ◽

Supercritical Phase ◽

Supercritical Solution ◽

Asymmetric Stretch ◽

Two Dimensional Infrared Spectroscopy ◽

Vibrational Equilibrium

Ultrafast 2DIR spectra and pump-probe responses of the N2O n 3 asymmetric stretch in SF6 as a function of density from the gas to supercritical phase and liquid are reported. 2DIR spectra unequivocally reveal free rotor character at all densities studied in the gas and supercritical region. Analysis of the 2DIR spectra determines that J-scrambling or rotational relaxation in N2O is highly efficient, occurring in ~1.5 to ~2 collisions with SF6 at all non-liquid densities. In contrast, N2O n 3 vibrational energy relaxation requires ~15 collisions, and complete vibrational equilibrium occurs on the ~ns scale at all densities. An independent binary collision model is sufficient to describe these supercritical state point dynamics. The N2O n 3 in liquid SF6 2DIR spectrum shows no evidence of free rotor character or spectral diffusion. Using these 2DIR results, hindered rotor or liquid-like character is found in gas and all supercritical solutions for SF6 densities ³ r * = 0.3, and increases with SF6 density. 2DIR spectral analysis offers direct time domain evidence of critical slowing for SF6 solutions closest to the critical point density. Applications of 2DIR to other high density and supercritical solution dynamics and descriptions are discussed. <br>

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Resonance Enhanced Multiphoton Ionization Spectra of Molecules and Molecular Fragments and Femtosecond Energy- and Angle-Resolved Pump-Probe Photoelectron Spectra

10.21236/ada359973 ◽

1998 ◽

Author(s):

Vincent McKoy

Keyword(s):

Multiphoton Ionization ◽

Photoelectron Spectra ◽

Molecular Fragments ◽

Pump Probe

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Strong coupling: resonant effects

10.1093/oso/9780198782995.003.0007 ◽

2017 ◽

Author(s):

Alexey V. Kavokin ◽

Jeremy J. Baumberg ◽

Guillaume Malpuech ◽

Fabrice P. Laussy

Keyword(s):

Strong Coupling ◽

Experimental Studies ◽

Strong Coupling Regime ◽

Theoretical Studies ◽

Stimulated Scattering ◽

Quantum Theories ◽

Pump Probe ◽

Exciton Polaritons ◽

Linear Optical Properties ◽

Experimental And Theoretical Studies

This chapter presents experimental studies performed on planar semiconductor microcavities in the strong-coupling regime. The first section reviews linear experiments performed in the 1990s that evidence the linear optical properties of cavity exciton-polaritons. The chapter is then focused on experimental and theoretical studies of resonantly excited microcavity emission. We mainly describe experimental configuations in which stimulated scattering was observed due to formation of a dynamical condensate of polaritons. Pump-probe and cw experiments are described in addition. Dressing of the polariton dispersion and bistability of the polariton system due to inter-condensate interactions are discussed. The semiclassical and the quantum theories of these effects are presented and their results analysed. The potential for realization of devices is also discussed.

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Study of Brillouin optical time domain analysis fiber sensing with stabilized low-RIN pump-probe laser scheme

20th Italian National Conference on Photonic Technologies (Fotonica 2018) ◽

10.1049/cp.2018.1650 ◽

2018 ◽

Author(s):

L. Rossi ◽

D. Marini ◽

F. Bastianini ◽

G. Bolognini

Keyword(s):

Time Domain ◽

Time Domain Analysis ◽

Domain Analysis ◽

Probe Laser ◽

Pump Probe ◽

Fiber Sensing ◽

Optical Time

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Criteria for Assessing the Interlayer Coupling of van der Waals Heterostructures Using Ultrafast Pump–Probe Photoluminescence Spectroscopy

ACS Nano ◽

10.1021/acsnano.1c01787 ◽

2021 ◽

Author(s):

Shuangping Han ◽

Xilong Liang ◽

Chengbing Qin ◽

Yan Gao ◽

Yunrui Song ◽

...

Keyword(s):

Van Der Waals ◽

Interlayer Coupling ◽

Photoluminescence Spectroscopy ◽

Van Der Waals Heterostructures ◽

Pump Probe

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Ultrafast Electron/Energy Transfer and Intersystem Crossing Mechanisms in BODIPY-Porphyrin Compounds

Processes ◽

10.3390/pr9020312 ◽

2021 ◽

Vol 9 (2) ◽

pp. 312

Author(s):

Yusuf Tutel ◽

Gökhan Sevinç ◽

Betül Küçüköz ◽

Elif Akhuseyin Yildiz ◽

Ahmet Karatay ◽

...

Keyword(s):

Energy Transfer ◽

Fluorescence Spectra ◽

Visible Region ◽

Energy Transfer Mechanism ◽

Free Base ◽

Pump Probe ◽

Harvesting Efficiency ◽

Probe Spectroscopy ◽

Absorption Features ◽

Transfer Mechanisms

Meso-substituted borondipyrromethene (BODIPY)-porphyrin compounds that include free base porphyrin with two different numbers of BODIPY groups (BDP-TTP and 3BDP-TTP) were designed and synthesized to analyze intramolecular energy transfer mechanisms of meso-substituted BODIPY-porphyrin dyads and the effect of the different numbers of BODIPY groups connected to free-base porphyrin on the energy transfer mechanism. Absorption spectra of BODIPY-porphyrin conjugates showed wide absorption features in the visible region, and that is highly valuable to increase light-harvesting efficiency. Fluorescence spectra of the studied compounds proved that BODIPY emission intensity decreased upon the photoexcitation of the BODIPY core, due to the energy transfer from BODIPY unit to porphyrin. In addition, ultrafast pump-probe spectroscopy measurements indicated that the energy transfer of the 3BDP-TTP compound (about 3 ps) is faster than the BDP-TTP compound (about 22 ps). Since the BODIPY core directly binds to the porphyrin unit, rapid energy transfer was seen for both compounds. Thus, the energy transfer rate increased with an increasing number of BODIPY moiety connected to free-base porphyrin.

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