Condensed Matter Seminar Series
Ho Bun Chan
University of Florida Gainesville
Tuesday June 19, 11:30 am, Room 298, Physics Building
Abstract: As micro and nanomechanical structures continue to shrink in size,
fluctuation effects become increasingly important in their operation.
The Casimir force, for example, originates from the zero-point quantum
fluctuations of the electromagnetic field and the boundary conditions
imposed by conducting surfaces. We demonstrated the Casimir effect
using a micromechanical torsional oscillator. Ongoing efforts aim
at measuring the nontrivial boundary dependence of the Casimir force.
I will also describe other phenomena that arise from the interplay
between fluctuations and nonlinearity. Under strong periodic drive, a
nonlinear micromechanical oscillator develops bistability. Fluctuations
induce switching between the coexisting dynamical states. We observed
a wide range of generic phenomena, including universal scaling of the
activation barrier near bifurcation points and the occurrence of
kinetic phase transition at comparable state occupations.
Host: Gleb Finkelstein