Tatarkova Svetlana A, Sibbett Wilson, Dholakia Kishan
School of Physics & Astronomy, University of St. Andrews, North Haugh, St. Andrews, Fife, KY16 9SS, Scotland.
Phys Rev Lett. 2003 Jul 18;91(3):038101. doi: 10.1103/PhysRevLett.91.038101. Epub 2003 Jul 15.
Experimental observations of the fluctuation-driven net transport of silica microspheres are presented in a two-dimensional optical potential of circular symmetry created by a Bessel light beam. The optical field is tailored to break symmetry and create a static tilted periodic (washboard) potential. As the tilt of potential exceeds a threshold, a transition between locked and running modes is observed. The running mode manifests itself by the rapid accumulation of particles at the beam center.
