AFM trajectory java simulator

In an effort to aid in the understanding of the nonlinear dynamics of the trajectories followed by an Atomic Force Microscope (AFM), I have written an interactive java applet simulator using a simple inelastic billiard model developed by Predrag Cvitanović and Rytis Paškauskas. We study the trajectories followed by the tip of the AFM as a function of its physical parameters and initial conditions.

The model represents the AFM as the addition of two harmonic oscillators vibrating independently in the vertical and horizontal planes. The moving surface imaged by the AFM is modeled as a time-periodic sinusoid. The attractors in this system can be strange attractors (recurrent and aperiodic), stable periodic trajectories, and attracting or 2-tori. Once we have an idea of the nature of these attractors, we iterate points in their phase space vicinity to estimate their basins of attraction. We also study the basic topology of the various attractors produced in this system.

The simulator is useful in developing intuition about the long term behaviors of different AFM setups, and might also be helpful in developing new techniques for imaging clean periodic surfaces by atomic force friction microscopy. The program is open source [download].

Warning: you will have to exit the browser to stop the java simulator

[A fix, Siddharta Dec 6 2006: the path to Firefox (/opt/MozillaFirefox in SuSE) is possibly not included in the dynamic linking library file /etc/ld.so.conf. Adding it here and then running ldconfig can solve all problems with Firefox plugins! I should get a Fields Medal for this.]

AFM Java Simulator [stable 02/06/2006] [source]


AFM Java Simulator [unstable 05/30/2006] [source]


Manual: Simulation of tapping mode trajectories in an AFM [12/25/2005]