Berlin 2005 – wissenschaftliches Programm
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DY: Dynamik und Statistische Physik
DY 43: Einstein Symposium Brownian Motion, Diffusion and Beyond (SYBM) – Contributed Talks I
DY 43.9: Vortrag
Dienstag, 8. März 2005, 16:30–16:45, TU H2032
Recurrence and Photon Statistics in Fluorescence Fluctuation Spectroscopy — •Christian Hübner1, Johannes Hohlbein1,2, and Gert Zumofen3 — 1Universität Halle, Fachbereich Physik, Hoher Weg 8, 06120 Halle — 2Max-Planck-Institut für Mikrostrukturphysik, Weinberg2, 06120 Halle — 3Eidgenössische Technische Hochschule Zürich, Physikalische Chemie, 8093 Zürich
We report on fluorescence fluctuations of nanoparticles diffusing through a laser focus. Subject to an intensity threshold the fluorescence signal is transformed into time traces of on- and off-periods. The distribution functions of the experimental on- and off-times follow power laws t−α over several orders of magnitude with exponents α ≃ 1.5 − 2. At long times the distribution functions cross over to exponential decays. For the interpretation of the experimental data a diffusion-reaction equation is proposed which covers both, the diffusion controlled recurrence and the photon statistics as the relevant processes.