Abstract
Understanding mechanisms for rectifying stochastic fluctuations has been a long-standing problem in nonequilibrium statistical mechanics. Here, we explore an opportunity provided by nonequilibrium parity-violating metamaterials to uncover new mechanisms for rectification of energy and motion. Using a parity-violating gyroscopic metamaterial that is allowed to interact with a bath of active particles as a model system, we develop an analytic diagrammatic theory that compactly elucidates how the rectification results from an interplay between gyroscopic forces, nonequilibrium activity, and network structure. Our active metamaterial model can generate energy flows through an object in the absence of any temperature gradient. The nonreciprocal microscopic fluctuations responsible for generating the energy flows can further be used to power locomotion in, or exert forces on, a viscous fluid. Taken together, our analytical and numerical results elucidate how the geometry and interparticle interactions of the parity-violating material can couple with the nonequilibrium fluctuations of an active bath and enable rectification of energy and motion.
3 More- Received 5 September 2019
- Revised 5 March 2020
- Accepted 26 March 2020
DOI:https://doi.org/10.1103/PhysRevX.10.021036
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Popular Summary
Identifying mechanisms that rectify stochastic fluctuations is a long-standing and important problem in nonequilibrium statistical mechanics. While studies of biological motor proteins and other related advances have shown how stochastic fluctuations can be rectified to power-directed motion, directed energy transport remains less well explored. Here, using a model metamaterial, we explore strategies to achieve directed energy transport, even in the absence of temperature biases.
Our platform is a spring-mass-type network model where the particles are further subject to magnetic forces and are allowed to interact with a bath of active energy-consuming particles. Our analytical and numerical results elucidate how the geometry of the network, the magnetic field, and the interactions with the active bath can couple to support net energy transport between sites even in the absence of any temperature gradients.
Together, our results can provide new strategies for rectification of energy and motion at the microscale, as well as a theoretical framework to understand similar rectification processes.