Substituent positional effect on radiative lifetimes of anthracene sulphonates

Excited state lifetimes of anthracene-1-sulphonate, anthracene-2-sulphonate, anthracene-1,5-disulphonate, and anthracene-1,8-disulphonate have been studied by photoselection and single photon counting methods. Experimental lifetimes are compared with theoretical values. For anthracene- monosulphonates, exciplex formation with water is proposed. In the case of anthracene-1,8-disulphonate, distortion in molecular geometry is found responsible for the higher non-radiative decay constant. Summation of nonradiative decay constants, Σki, increase in the series [Formula: see text]. The sharp increase for 1,8-AS is perhaps due to distortion of the molecular geometry due to steric effect of two bulky and charged —SO3− groups on the same side of the anthracene skeleton.

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Single Particle Spectroscopy of Radiative Processes in Colloid-to-Film-Coupled Nanoantennas

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2018-1109 ◽

2018 ◽

Vol 232 (9-11) ◽

pp. 1593-1606 ◽

Cited By ~ 6

Author(s):

Max J. Schnepf ◽

Yannic Brasse ◽

Fabian R. Goßler ◽

Anja Maria Steiner ◽

Julian Obermeier ◽

...

Keyword(s):

Single Particle ◽

Radiative Decay ◽

Single Photon ◽

Photon Counting ◽

Life Time ◽

Fluorescence Decay ◽

Decay Rates ◽

Single Photon Counting ◽

Radiative Processes ◽

Particle Level

Abstract We present a fluorescent emitter (rhodamine B) coupled to a dielectric or metallic interface as well as a metallic cavity to study their radiative decay processes. Supported by finite-difference time-domain (FDTD) simulations, we correlate the non-radiative and radiative decay rates with the absorption and scattering cross section efficiencies, respectively. On a single particle level, we use atomic force microscopy (AFM), scanning electron microscopy (SEM), scattering spectroscopy, fluorescence life time imaging (FLIM) and time-correlated single photon counting (TCSPC) to evaluate the enhanced fluorescence decay at the same location. With this study, we show a colloidal gain material, which can be integrated into lattices using existing directed self-assembled methods to study their coherent energy transfer.

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Single Point PICA Probing with an Avalanche Photo-Diode

ISTFA 2001: Conference Proceedings from the 27th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2001p0023 ◽

2001 ◽

Author(s):

Mike Bruce ◽

Rama R. Goruganthu ◽

Shawn McBride ◽

David Bethke ◽

J.M. Chin

Keyword(s):

Single Photon ◽

Single Point ◽

Photon Counting ◽

Ring Oscillator ◽

Time Resolved ◽

Single Photon Counting ◽

Photo Diode ◽

Avalanche Photo Diode ◽

Photo Multiplier Tube ◽

Channel Plate

Abstract For time resolved hot carrier emission from the backside, an alternate approach is demonstrated termed single point PICA. The single point approach records time resolved emission from an individual transistor using time-correlated-single-photon counting and an avalanche photo-diode. The avalanche photo-diode has a much higher quantum efficiency than micro-channel plate photo-multiplier tube based imaging cameras typically used in earlier approaches. The basic system is described and demonstrated from the backside on a ring oscillator circuit.

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UVscope and its application aboard the ASTRI-Horn telescope

Experimental Astronomy ◽

10.1007/s10686-021-09728-6 ◽

2021 ◽

Author(s):

Maria Concetta Maccarone ◽

Giovanni La Rosa ◽

Osvaldo Catalano ◽

Salvo Giarrusso ◽

Alberto Segreto ◽

...

Keyword(s):

Gamma Ray ◽

Single Photon ◽

Photon Counting ◽

Light Flux ◽

Cosmic Ray ◽

High Energy ◽

Wide Field ◽

High Energy Astrophysics ◽

Single Photon Counting ◽

Photon Counting Mode

AbstractUVscope is an instrument, based on a multi-pixel photon detector, developed to support experimental activities for high-energy astrophysics and cosmic ray research. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650 nm. The instrument can be used in a wide field of applications where the knowledge of the nocturnal environmental luminosity is required. Currently, one UVscope instrument is allocated onto the external structure of the ASTRI-Horn Cherenkov telescope devoted to the gamma-ray astronomy at very high energies. Being co-aligned with the ASTRI-Horn camera axis, UVscope can measure the diffuse emission of the night sky background simultaneously with the ASTRI-Horn camera, without any interference with the main telescope data taking procedures. UVscope is properly calibrated and it is used as an independent reference instrument for test and diagnostic of the novel ASTRI-Horn telescope.

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