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Published on: August 26, 2015
Experimental control of transport and current reversals in a deterministic optical rocking ratchet
Alejandro V Arzola1, Karen Volke-Sepúlveda, José L Mateos
1Instituto de Física, Universidad Nacional Autónoma de México, México, Distrito Federal, Mexico. avarzola@gmail.com
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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