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The authors studied ultrafast relaxation of localized excited states at Ge-related O deficient centers in SiO2 using femtosecond transient-absorption spectroscopy. The relaxation dynamics exhibits a biexponential decay, which the authors ascribe to the dep ...
A review. The crucial steps of cellular photoperception are characterized and followed in real time by laser spectroscopy down to a few tens of femtoseconds. The photoactive proteins studied here are involved in major natural processes such as vision (bact ...
The excited-state dynamics of a series of electron donor−acceptor bridged systems (DABS) consisting of a boron−dipyrromethene chromophore covalently linked to a dinitro-substituted triptycene has been investigated using femtosecond time-resolved spectrosco ...
Coupling the emitted light from single quantum dots into an optic fiber has been demonstrated as a. plug and play' single-photon Source. In this work, lifetime dynamics measurements were performed with two time-delayed femtosecond optical pulses at differe ...
A review. Time-resolved X-ray absorption fine structure (XAFS) spectroscopy with picosecond temporal resoln. is a new method to observe electronic and geometric structures of short-lived reaction intermediates. It combines an intense femtosecond laser sour ...
We present a comparative study of ultrafast photoconversion dynamics in tetracene (Tc) and pentacene (Pc) single crystals and Pc films using optical pump-probe spectroscopy. Photoinduced absorption in Tc and Pc crystals is activated and temperature-indepen ...
Photoexcitation of the Mott insulator 1T-TaS2 by an intense laser pulse leads to an ultrafast transition toward a gapless phase. Besides the collapse of the electronic gap, the sudden excitation of the charge density wave (CDW) mode results in periodic osc ...
We investigate here the mechanism of collisionally-enhanced isotopic selectivity observed in infrared multiple photon dissociation (IRMPD) of vibrationally pre-excited CF3H by Boyarkin et al. (J. Chem. Phys. 118, 93 (2003)). For both the carbon-12 and carb ...
The authors report a femtosecond pump-probe study of photochem. of concd. aq. solns. of [Ru(bpy)3]2+, as a function of pump power (up to 2 TW/cm2) at 400 nm excitation. The transient absorption spectra in the 345-660 nm range up to 1 ns time delay enable t ...
We report an experimental demonstration of optical parametric generation in a periodically poled KTiOP O4 crystal based on the principle of mirrorless optical parametric oscillation. A femtosecond pump pulse spectrally centered at 792 nm from a Ti:sapphire ...