Time-Resolved Spectral Measurement of Dendrimer Molecular Films with Rhodamine B Core

2001 ◽  
Vol 708 ◽  
Author(s):  
M. Zhou ◽  
A. Otomo ◽  
S. Yokoyama ◽  
S. Mashiko
Keyword(s):  
Rhodamine B ◽  
Stimulated Emission ◽  
Pump Light ◽  
Molecular Films ◽  
Fast Decay ◽  
Probe Light ◽  
Time Resolved ◽  
Pump Probe ◽  
Molecular Density ◽  
Molecular Film

ABSTRACTWe investigated molecular thin films fabricated using novel organic materials, such as dendrimers with a rhodamine B (Rh-B) core, by a pump-probe measurement for ultrafast time-resolved spectroscopy with a time resolution of approximately 160 fs. The photon energy transfer caused by the interaction of the dendrimer molecules was measured in terms of absorbance. The wavelength of the pump light was 550 nm and a white continuum light spanning from 450 nm to 750 nm was used as a probe light. A spin-coated molecular film made of dendrimer molecules with Rh-B core has a relatively high molecular density. We measured a strong stimulated emission at a wavelength of 612 nm, whose fast decay was assumed to be caused by intermolecular interactions between the dendrimer molecules with Rh-B core. The lifetime of the molecules in the excited state was measured to be as short as 10 ps. Several types of molecular films with different molecular densities were compared, and cases with different pump energies were also discussed.

Spectroscopic Techniques using Synchrotron Radiation and Free-Electron and Conventional Lasers

1998 ◽  
Vol 5 (3) ◽  
pp. 293-298 ◽  
Author(s):  
A. Tadjeddine ◽  
A. Peremans ◽  
A. Le Rille ◽  
W. Q. Zheng ◽  
J. M. Ortéga ◽  
...  
Keyword(s):  
Synchrotron Radiation ◽  
Quantum Wells ◽  
Storage Ring ◽  
Free Electron ◽  
Difference Frequency Generation ◽  
Stimulated Emission ◽  
Vibrational Properties ◽  
Spectroscopic Techniques ◽  
Time Resolved ◽  
Pump Probe

Considerable progress in the investigation of the electronic and vibrational properties of atoms, molecules, materials, surfaces and interfaces has been achieved by combining different photon sources of complementary characteristics. In this paper some experimental results obtained recently at LURE by using two synchronized sources, such as the IR free-electron laser (FEL) CLIO, the VUV storage ring FEL, synchrotron radiation and table lasers, are presented. Using CLIO synchronized with a YAG laser allows the investigation of the vibrational properties of adsorbed species by the non-linear optical technique of visible–IR sum (difference) frequency generation, as shown for the adsorption of hydrogen on platinum in the electrochemical environment. The second result reported here relates to the study of the intersubband stimulated emission in GaAs/GaAlAs quantum wells by pump-probe experiments using the two-colour configuration of CLIO. The combination of a mode-locked Ar+ laser and synchrotron radiation has been used for investigations in a pump-probe arrangement of the ionization of Xe atoms via the resonant state Xe* 5p 55d [3/2]1. The final example is a time-resolved core-level spectroscopy study of photoexcited Si(111) 2 × 1 surfaces by using a combination of the naturally synchronized UV storage ring laser and synchrotron radiation.

scholarly journals Time-Resolved Polarization Imaging By Pump-Probe (Stimulated Emission) Fluorescence Microscopy

2000 ◽  
Vol 79 (1) ◽  
pp. 536-549 ◽  
Author(s):  
Ch. Buehler ◽  
C.Y. Dong ◽  
P.T.C. So ◽  
T. French ◽  
E. Gratton
Keyword(s):  
Fluorescence Microscopy ◽  
Stimulated Emission ◽  
Time Resolved ◽  
Polarization Imaging ◽  
Pump Probe

Time-resolved stimulated emission spectroscopy in the ultrashort domain through pump–probe experiments

2007 ◽  
Vol 254 (4) ◽  
pp. 859-862 ◽  
Author(s):  
S. Orlando ◽  
A. Paladini ◽  
L. Guidoni ◽  
A. Santagata ◽  
G.P. Parisi ◽  
...  
Keyword(s):  
Emission Spectroscopy ◽  
Stimulated Emission ◽  
Time Resolved ◽  
Pump Probe

Pump-Probe Measurements Using Silicon Nanocrystal Waveguides

2003 ◽  
Vol 770 ◽  
Author(s):  
Nathanael Smith ◽  
Max J. Lederer ◽  
Marek Samoc ◽  
Barry Luther-Davies ◽  
Robert G. Elliman
Keyword(s):  
Probe Beam ◽  
Time Resolution ◽  
Pump Beam ◽  
Silicon Nanocrystals ◽  
Continuous Wave ◽  
Optical Gain ◽  
Optical Pump ◽  
Time Resolved ◽  
Pump Probe ◽  
Probe Measurements

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.

Investigation on nonlinear dynamics of ZnO using time-resolved pump-probe technique with phase object

2011 ◽  
Author(s):  
Lirong Ge ◽  
Min Shui ◽  
Xiao Jin ◽  
Zhongguo Li ◽  
Yinglin Song
Keyword(s):  
Nonlinear Dynamics ◽  
Phase Object ◽  
Time Resolved ◽  
Pump Probe ◽  
Probe Technique

Light Emission Properties of GaN-Based Double Heterostructures and Quantum Wells

1995 ◽  
Vol 395 ◽  
Author(s):  
D.A.S. Loeber ◽  
J.M. Redwing ◽  
N.G. Anderson ◽  
M.A. Tischler
Keyword(s):  
Quantum Well ◽  
Quantum Wells ◽  
Stimulated Emission ◽  
Pump Light ◽  
Band Edge Emission ◽  
Emission Characteristics ◽  
Nitrogen Laser ◽  
Edge Emission ◽  
Edge Luminescence ◽  
Double Heterostructures

ABSTRACTEdge emission characteristics of optically pumped GaN-AlGaN double heterostructures and quantum wells are examined. The samples, which were grown by metalorganic vapor phase epitaxy, are photoexcited with light from a pulsed nitrogen laser. The pump light is focused to a narrow stripe on the sample surface, oriented perpendicular to a cleaved edge, and the edge luminescence is collected and analyzed. We first compare emission characteristics of highly excited GaN-AlGaN double heterostructures grown simultaneously on SiC and sapphire substrates. Polarization resolved spectral properties of edge luminescence from both structures is studied as a function of pump intensity and excitation stripe length. Characteristics indicative of stimulated emission are observed, particularly in the sample grown on SiC. We then present results demonstrating laser emission from a GaN-AlGaN separate-confinement quantum-well heterostructure. At high pump intensities, band edge emission from the quantum well exhibits five narrow (∼1 Å) modes which are evenly spaced by 10Å to within the resolution of the spectrometer. This represents the first demonstration of laser action in a GaN-based quantum-well structure.

scholarly journals Time-resolved photoluminescence study of the stimulated emission in ZnO nanoneedles

2005 ◽  
Vol 87 (9) ◽  
pp. 093108 ◽  
Author(s):  
W. M. Kwok ◽  
A. B. Djurišić ◽  
Y. H. Leung ◽  
W. K. Chan ◽  
D. L. Phillips
Keyword(s):  
Stimulated Emission ◽  
Time Resolved ◽  
Photoluminescence Study ◽  
Time Resolved Photoluminescence

scholarly journals Selective time-dependent changes of Cu(DPPE)(DMP)·PF6on photoexcitation

2014 ◽  
Vol 70 (a1) ◽  
pp. C776-C776 ◽  
Author(s):  
Elzbieta Trzop ◽  
Bertrand Fournier ◽  
Katarzyna Jarzembska ◽  
Jesse Sokolow ◽  
Radoslaw Kaminski ◽  
...  
Keyword(s):  
Structural Changes ◽  
Dye Sensitized Solar Cells ◽  
Department Of Energy ◽  
Data Sets ◽  
Monoclinic System ◽  
Time Resolved ◽  
Pump Probe ◽  
Light Emitting Devices ◽  
Potential Applications ◽  
Photon Source

Thanks to their potential applications as light-emitting devices, chemical sensors and dye-sensitized solar cells, heteroleptic copper (I) complexes have been extensively studied. Cu(DPPE)(DMP)·PF6(dppe= 1,2-bis(diphenylphosphino)ethane; dmp = 2,9-dimethyl-1,10-phenanthroline) crystallizes in the monoclinic system, P21/c, with two independent molecules in the asymmetric unit. Previous studies on this system [1,2] show strong temperature-dependent emission. The complex was studied at 90K under 355nm laser excitation. At this temperature, the luminescence decay for Cu(DPPE)(DMP)·PF6is biexponential with lifetimes of ~3μs and ~28μs. Two time-resolved X-ray diffraction techniques were applied for studies: (1) a Laue technique at BioCARS ID-14 beamline at the Advanced Photon Source, and (2) monochromatic diffraction at a newly constructed in-house pump-probe monochromatic facility at the University at Buffalo. Structural changes determined with the two methods are in qualitative agreement; discrepancies in position of the Cu and P atoms were observed. The molecular distortions were smaller than those determined at 16K in the earlier synchrotron study by Vorontsov et al. [2]. Photodeformation maps (see Figure below), in which the increase in temperature on photoexcitation has been eliminated, clearly illustrate the photoinduced atomic shifts for both data sets. Results will be compared with those obtained for other studied heteroleptic copper (I) complexes, for instance Cu[(1,10-phenanthroline-N,N′) bis(triphenylphosphine)]·BF4[3]. The in-house pump-probe facility is discussed by Radoslaw Kaminski at this meeting. Research funded by the National Science Foundation (CHE1213223). BioCARS Sector 14 at APS is supported by NIH (RR007707). The Advanced Photon Source is funded by the Office of Basic Energy Sciences, U.S. Department of Energy, (W-31-109-ENG-38). KNJ is supported by the Polish Ministry of Science and Higher Education through the "Mobility Plus" program.

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