title: Mechanical Autonomous Stochastic Heat Engine.
abstract: Stochastic heat engines are devices that generate work from random thermal motion using a small number of highly fluctuating degrees of freedom. Proposals for such devices have existed for more than a century and include the Maxwell demon and the Feynman ratchet. Only recently have they been demonstrated experimentally, using, e.g., thermal cycles implemented in optical traps. However, recent experimental demonstrations of classical stochastic heat engines are nonautonomous, since they require an external control system that prescribes a heating and cooling cycle and consume more energy than they produce. We present a heat engine consisting of three coupled mechanical resonators (two ribbons and a cantilever) subject to a stochastic drive. The engine uses geometric nonlinearities in the resonating ribbons to autonomously convert a random excitation into a low-entropy, nonpassive oscillation of the cantilever. The engine presents the anomalous heat transport property of negative thermal conductivity, consisting in the ability to passively transfer energy from a cold reservoir to a hot reservoir.
authors.affiliation: Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH), 8092 Zürich, Switzerland.
authors.forename: Marc
authors.initials: M
authors.lastname: Serra-Garcia
authors.affiliation: Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH), 8092 Zürich, Switzerland.
authors.forename: André
authors.initials: A
authors.lastname: Foehr
authors.affiliation: Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH), 8092 Zürich, Switzerland.
authors.forename: Miguel
authors.initials: M
authors.lastname: Molerón
authors.affiliation: Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH), 8092 Zürich, Switzerland.
authors.forename: Joseph
authors.initials: J
authors.lastname: Lydon
authors.affiliation: Department of Mathematics, Bowdoin College, Brunswick, Maine 04011, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Chong
authors.affiliation: Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology (ETH), 8092 Zürich, Switzerland.|Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: Chiara
authors.initials: C
authors.lastname: Daraio