Hannover 2013 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 35: Poster I
Q 35.85: Poster
Dienstag, 19. März 2013, 16:00–18:30, Empore Lichthof
Nonlinear response of an optomechanical system studied via the noise power spectrum — •Gotthold Fläschner1,2, Kai Ruschmeier1, Mohammad Reza Bakhtiari2, Alexander Schwarz1, Roland Wiesendanger1, and Michael Thorwart2 — 1Institute of Applied Physics and Center of Microstructure Research, University of Hamburg, Jungiusstrasse 11, 20355 Hamburg, Germany — 2I. Institute of Theoretical Physics, University of Hamburg, Jungiusstrasse 9, 20355 Hamburg, Germany
Utilizing a fiber optical Fabry-Perot interferometer is one way to detect the cantilever deflection in an atomic force microscopy set-up. Cantilever and fiber end form a low finesse cavity. The temperature of such a cantilever, which constitutes a micron sized mechanical oscillator, can be in principle determined by recording the power spectral density.
However, in the current experiment with a metal-coated cantilever, the spectral response function differs from the simple Lorentzian shape. In particular, its line shape is asymmetric and even shows antiresonant behavior due to the coupling of cavity and oscillator. We attribute this effect to a subtle interplay of different noises, which generates a nontrivial response of this nonlinear system. We analyze a tractable theoretical model and compare its predictions with experimental data. Its implications on accurate temperature measurement schemes are discussed.