Picosecond dynamics of excitations studied in three generations
نویسندگان
چکیده
X Ž . Picosecond fluorescence decay is observed in a new family of dendrimers constructed from 4,4 -bis diphenylamino stilbene repeat units. The rate of the decay is shown to depend on detection wavelength and the generation number in such a way that the energy of accepting states gradually lowers with the generation number. These observations can be consistently described in terms of the fast energy transfer from initially created localized states to more delocalized ones. q 2000 Elsevier Science B.V. All rights reserved.
منابع مشابه
Picosecond dynamics of excitations in light-harvesting complex B800-850 from Chromatium minutissimum studied using fluorescence spectrochronography.
The picosecond dynamics of excitations in the isolated B800-850 light-harvesting complex of the purple sulfur bacterium Chromatium minutissimum has been studied using picosecond fluorescence spectrochronography. A short-lived component of about 20 ps lifetime has been found at 77K at the short wavelength part of the B850 fluorescence spectrum similar to that previously described for the core an...
متن کاملEvaluation of Turbulence on the Dynamics of Monopile Offshore Wind Turbine under the Wave and Wind Excitations
In recent years, the use of offshore wind turbines has been considered on the agenda of the countries which have a significant maritime boundary due to more speed and stability of wind at sea. The aim of this study is to investigate the effect of wind turbulence on the aero-hydrodynamic behavior of offshore wind turbines with a monopile platform. Since in the sea, the wind turbine structures ar...
متن کاملExcitation Dynamics in Disubstituted Polyacetylene
We studied the excitation dynamics in films of disubstituted polyacetylene, a degenerate groundstate conjugated polymer, using psec transient and steady-state spectroscopies. The polymer is found to support charged and neutral topological soliton excitations concurrent with a strong intrinsic photoluminescence band with quantum efficiency, h . 50%. This leads to stimulated emission in thin film...
متن کاملPerspective: On the relevance of slower-than-femtosecond time scales in chemical structural-dynamics studies
A number of examples illustrate structural-dynamics studies of picosecond and slower photo-induced processes. They include molecular rearrangements and excitations. The information that can be obtained from such studies is discussed. The results are complementary to the information obtained from femtosecond studies. The point is made that all pertinent time scales should be covered to obtain co...
متن کاملDimensionality dependence of optical nonlinearity and relaxation dynamics in cuprates
Femtosecond pump-probe measurements find pronounced dimensionality dependence of the optical nonlinearity in cuprates. Although the coherent twophoton absorption (TPA) and linear absorption bands nearly overlap in both quasi-one and two-dimensional (1D and 2D) cuprates, the TPA coefficient is one order of magnitude smaller in 2D than in 1D. Furthermore, picosecond recovery of optical transparen...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2000