标题： 饥饿的恶魔：能量收集主动粒子必须遵守热力学第二定律 显示英文标题

标题： The Hungry Daemon: An energy-harvesting active particle must obey the Second Law of Thermodynamics

摘要： 类似麦克斯韦妖或费曼-斯莫卢霍夫斯基摆轮这样的思想实验有助于探索热力学第二定律的微观起源。 这里我们提出一个比摆轮更复杂的物理系统，该系统由一个哈密顿活性粒子组成，该粒子可以从可能处于单一温度热平衡环境中的环境中获取能量。 我们表明，尽管现象学描述似乎允许该系统作为第二类永动机运行，但完整的机械分析确认这是不可能的，而且只有当环境具有类似于激光介质的能量反演分布时，才能实现持续的能量收集。 显示英文摘要

摘要： Thought experiments like Maxwell's Demon or the Feynman-Smoluchowski Ratchet can help in pursuing the microscopic origin of the Second Law of Thermodynamics. Here we present a more sophisticated physical system than a ratchet, consisting of a Hamiltonian active particle which can harvest energy from an environment which may be in thermal equilibrium at a single temperature. We show that while a phenomenological description would seem to allow the system to operate as a Perpetual Motion Machine of the Second Kind, a full mechanical analysis confirms that this is impossible, and that perpetual energy harvesting can only occur if the environment has an energetic population inversion similar to a lasing medium.