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Phase Dependent Vectorial Current Control in Symmetric Noisy Optical Ratchets.
Magda G Sánchez-Sánchez1, Roberto de J León-Montiel1, Pedro A Quinto-Su1
1Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, 04510 Cd. Mx., México.
Physical Review Letters
|November 9, 2019
Summary
We achieved directed microparticle transport using a noisy optical ratchet. The motion
Area of Science:
- Physics
- Optical Trapping
- Microparticle Manipulation
Background:
- Optical ratchets enable directed particle motion.
- Symmetry breaking is crucial for directed transport.
Purpose of the Study:
- To demonstrate single microparticle transport in a symmetric noisy optical ratchet.
- To investigate the influence of dynamic potentials and forces on particle movement.
Main Methods:
- Utilized a linear array of 20 symmetric 3D optical traps.
- Applied dynamic external force and time-varying optical potential depths.
- Introduced uncorrelated noise in potential depths and a periodic external force.
Main Results:
- Achieved directed microparticle transport.
- Demonstrated that motion direction and speed depend on the phase difference between noise and force.
- Symmetry breaking at specific timescales enables directed motion.
Conclusions:
- Single microparticle transport is controllable in a symmetric noisy optical ratchet.
- Phase control between dynamic potentials and external force is key for directed motion.
- This work offers insights into stochastic transport phenomena.
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