title: Work fluctuations in a nonlinear micromechanical oscillator driven far from thermal equilibrium.
abstract: We explore fluctuation relations in a periodically driven micromechanical torsional oscillator. In the linear regime where the modulation is weak, we verify that the ratio of the work variance to the mean work is constant, consistent with conventional fluctuation theorems. We then increase the amplitude of the periodic drive so that the response becomes nonlinear and two nonequilibrium oscillation states coexist. Due to interstate transitions, the work variance exhibits a peak at the driving frequency at which the occupation of the two states is equal. Moreover, the work fluctuations depend exponentially on the inverse noise intensity. Our data are consistent with recent theories on systems driven into bistability that predict generic behaviors different from conventional fluctuation theorems.
authors.affiliation: Department of Physics, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: P
authors.initials: P
authors.lastname: Zhou
authors.affiliation: Department of Physics, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: X
authors.initials: X
authors.lastname: Dong
authors.affiliation: Department of Physics, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: C
authors.initials: C
authors.lastname: Stambaugh
authors.affiliation: Department of Physics, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: H B
authors.initials: HB
authors.lastname: Chan