Berlin 2018 – scientific programme

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O: Fachverband Oberflächenphysik

O 97: Scanning probe techniques: Method development II

O 97.3: Talk

Thursday, March 15, 2018, 15:30–15:45, MA 005

Mapping Light-Induced Cantilever dynamics by Scanned Laser Radiation — •Sven Kraft, Dieter Schick, Semjon Köhnke, Boris Hage, Ingo Barke, and Sylvia Speller — University of Rostock, Institute of Physics, 18051 Rostock, Germany

Direct actuation of Atomic Force Microscopy (AFM) cantilevers by a laser beam is an alternative method to the widely used dither piezo actuator. In particular in the case of liquid environments laser actuation is beneficial because spurious oscillation modes, visible as the so called "Forest of peaks" [1], are avoided. Our aim is to better understand the mechanisms leading to the laser-induced oscillation, by revealing the dependence of the location of the laser spot on the cantilever. Analysis of spatially and frequency resolved data of different cantilevers indicate that a combination of mechanisms contributes to the total motion. Among them are thermal effects [2,3] and instantaneous forces from radiation pressure [4]. Besides these two we observe quasi-instantaneous thermal actuation forces for coated as well as uncoated cantilevers. The results may allow improved actuation schemes, reducing undesired effects such as cantilever heating.

[1] T. E. Schäffer, J. P. Cleveland, F. Ohnesorge, D. A. Walters, and P. K. Hansma, J Appl Phys 80, 3622 (1996)

[2] D. Ramos, J. Tamayo, J. Mertens, and M. Calleja, J Appl Phys 99, 124904 (2006)

[3] D. Kiracofe, K. Kabayashi, A. Labuda, A. Raman, H. Yamada, Review of Scientific Instruments 82, 013702 (2011)

[4] D. Kleckner, D.Bouwmeester, Nature 444(7115) (2006)