Heat conduction induced by non-Gaussian athermal fluctuations


Recent experimental developments in single-molecule manipulation have enabled us to investigate the detailed thermodynamic properties of small systems such as colloidal and biological systems [1]. If the environments of the systems are in thermal equilibrium, stochastic thermodynamics with Gaussian noises has shown to be very powerful to investigate universal relations in nonequilibrium statistical mechanics of small systems. On the other hand, the effects of non-Gaussian noises from athermal environments have been reported in electrical circuits [2] and biomolecular systems [3]. The conventional approaches in stochastic thermodynamics are not applicable to such systems, because the environments are not in thermal equilibrium. Then, how should the fundamental thermodynamic relations, such as the Fourier law and the heat fluctuation theorem, be modified with non-Gaussian noises?

In this presentation, we answer this question with a stochastic model of heat conduction induced by non-Gaussian noises from athermal environments on the basis of stochastic energetics [4-6]. We consider a non-Gaussian model of Brownian motor and derive generalizations of the Fourier law and the heat fluctuation theorem. Moreover, we investigate the validity of the zeroth law of thermodynamics for athermal systems, and find that the zeroth law is not universally valid but depends on the details of a contact device between two systems. We numerically verify our results, which demonstrate that the direction of the average heat current depends on the characteristics of the heat conductor, and that the properties of the heat fluctuation significantly deviates from those of the conventional fluctuation theorem.

[1] C. Bustamante, J. Liphardt, and F. Ritort, Phys. Today 58, No. 7, 43 (2005).
[2] Y. M. Blanter, M. Bu, D. P. Theh, and U. D. Gene, Phys. Rep. 336, 1 (2000).
[3] E. Ben-Isaac et al., Phys. Rev. Lett. 106, 238103 (2011).
[4] K. Sekimoto, J. Phys. Soc. Jpn. 66, 1234 (1997).
[5] K. Kanazawa, T. Sagawa, and H. Hayakawa, Phys. Rev. Lett. 108, 210601 (2012).
[6] K. Kanazawa, T. Sagawa, and H. Hayakawa, arXiv:1209.2222.

Designed by CSS.Design Sample