The equilibrium properties of a Janus fluid confined to a one-dimensional channel are exactly derived. The fluid is made of particles with two faces (active and passive), so that the pair interaction is that of hard spheres, except if the two active faces are in front of each other, in which case the interaction has a square-well attractive tail. Our exact solution refers to quenched systems (i.e., each particle has a fixed face orientation), but we argue by means of statistical-mechanical tools that the results also apply to annealed systems (i.e., each particle can flip its orientation) in the thermodynamic limit. Comparison between theoretical results and Monte Carlo simulations for quenched and annealed systems, respectively, shows an excellent agreement.

中文翻译：

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一维 Janus 流体。从淬火系统到退火系统的精确解和映射

精确地导出了限制在一维通道中的 Janus 流体的平衡特性。流体由具有两个面（主动和被动）的粒子组成，因此配对相互作用是硬球的相互作用，除非两个主动面彼此在前面，在这种情况下，相互作用具有方阱吸引力尾巴。我们的精确解是指淬火系统（即每个粒子具有固定的面取向），但我们通过统计力学工具认为结果也适用于热力学中的退火系统（即每个粒子可以翻转其取向）限制。分别对淬火和退火系统的理论结果与蒙特卡罗模拟进行比较，显示出极好的一致性。