We report the study of femtosecond laser-induced air plasma fluorescence under the illumination of terahertz (THz) pulses. Semiclassical modeling and experimental verification indicate that time-resolved THz radiation-enhanced emission of fluorescence is dominated by the electron kinetics and the electron-impact excitation of gas molecules or ions. We demonstrate that the temporal waveform of t...

Controlling two-photon molecular fluorescence leading to selective fluorophore excitation has been a long sought after goal in fluorescence microscopy. In this letter, we thoroughly explore selective fluorescence suppression through simultaneous two-photon absorption by two different fluorophores followed by selective one-photon stimulated emission for one particular fluorophore. We achieve thi...

The fluorescence of colloidal CdSe/ZnS nanocrystals at room temperature exhibits a perfect antibunching under continuous or pulsed excitation. In this paper, we discuss the consequences of fluorescence properties of CdSe nanocrystals on the generation of single photons. In particular,we examine the role of Auger processes in the inhibition of multiexcitonic emission. We also discuss the relatio...

A flow injection system is reported for the determination of fluoride based on its effects on the fluorescence intensity of Al-morin complex at pH 3.0 in ethanol-warn mixture. The effect of important parameters such as excitation and emission wavelengths, pH, reagents concenkations, flow rate of the carrier stream, sample injection volume, time of measurepent and interferences are reported. ...

We describe the design, properties, and performance of an excitation–emission EE fluorimeter that enables spectral characterization of an object simultaneously with respect to both its excitation and its emission properties. Such devices require two wavelength-selecting elements, one in the optical path of the excitation broadband light to obtain tunable excitation and the other to analyze the ...

We experimentally investigate the fluorescence photon emission characteristics for single q-dots by using optical nanofibers. We demonstrate that single q-dots can be deposited along an optical nanofiber systematically and reproducibly with a precision of 5 μm. For single q-dots on an optical nanofiber, we measure the fluorescence photon numbers coupled into the nanofiber and the normalized pho...

The structure-property characteristics of a series of newly synthesized intramolecular chargetransfer (ICT) compounds, single-branch monomer with triphenylmethane as electron donor and 2,1,3-benzothiadiazole as acceptor, the corresponding two-branch dimer and threebranch trimer, have been investigated by means of steady-state and femtosecond timeresolved stimulated emission fluorescence depleti...

Excitation-dependent fluorophores (EDFs) have been attracted increasing attention owing to their high tunability of emissions and prospective applications ranging from multicolor patterning to bio-imaging. Here, we report tunable fluorescence with quenching dip induced by strong coupling of exciton and plasmon in the hybrid nanostructure of CTAB* EDFs and gold nanoparticles (AuNPs). The quenchi...