We address the question of transport of heat in out-of-equilibrium systems. The experimental setup consists in two coupled granular gas nonequilibrium steady-state (NESS) heat baths, in which Brownian-like rotors are imbedded. These rotors are electromechanically coupled, thanks to DC micromotors, through a resistor $R$ such that energy flows between them. The average flux depends linearly in the difference in the baths' temperature. Varying $R$ allows extrapolation in the nondissipative coupling limit ($R\to 0$). We show that in this limit the heat flux obeys the fluctuation theorem in a form proposed by Jarzynski and Wójcik in 2004 [C. Jarzynski and D. K. Wójcik, Phys. Rev. Lett. 92, 230602 (2004)] for the fluctuations of the flux between finite size equilibrium heat baths.

中文翻译：

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两个非平衡稳态恒温器之间的热通量的统计特性

我们解决不平衡系统中的热传递问题。实验装置包括两个耦合的粒状气体非平衡稳态（NESS）热浴，其中嵌入了布朗式转子。这些转子通过直流微电机通过电阻器机电耦合$\mathrm{[R}$使能量在它们之间流动。平均通量与浴温差成线性关系。变化的$\mathrm{[R}$ 允许外推非耗散耦合极限（$\mathrm{[R}\to 0$）。我们证明，在这个极限中，热通量遵循Jarzynski和Wójcik在2004年提出的形式[C. Jarzynski和DKWójcik，物理学。莱特牧师 92，230602（2004）]为有限尺寸平衡热浴之间的磁通的波动。