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arXiv · 1104.5171

Experimental Control of Transport and Current Reversals in a Deterministic Optical Rocking Ratchet

Alejandro V. Arzola·Karen Volke-Sepúlveda·José L. Mateos
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Abstract

We present an experimental demonstration of a deterministic optical rocking ratchet. A periodic and asymmetric light pattern is created to interact with dielectric microparticles in water, giving rise to a ratchet potential. The sample is moved with respect to the pattern with an unbiased time-periodic rocking function, which tilts the potential in alternating opposite directions. We obtain a current of particles whose direction can be controlled in real time and show that particles of different sizes may experience opposite currents. Moreover, we observed current reversals as a function of the magnitude and period of the rocking force.

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Alejandro V. Arzola, Karen Volke-Sepúlveda, José L. Mateos. 2011-04-27. Experimental Control of Transport and Current Reversals in a Deterministic Optical Rocking Ratchet. https://doi.org/10.1103/physrevlett.106.168104

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