We explore a variant of the Katz-Lebowitz-Spohn (KLS) driven lattice gas in two dimensions, where the lattice is split into two regions that are coupled to heat baths with distinct temperatures. The temperature boundaries are oriented parallel to the external particle drive. If the hopping rates at the interfaces satisfy particle-hole symmetry, the current difference across them generates a vector flow diagram akin to a vortex sheet. We have studied the finite-size scaling of the particle density fluctuations in both temperature regions, and observed that it is controlled by the respective temperature values. If the colder subsystem is maintained at the KLS critical temperature, while the hotter subsystem's temperature is set much higher, the interface current greatly suppresses particle exchange between the two regions. As a result of the ensuing effective subsystem decoupling, strong fluctuations persist in the critical region, whence the particle density fluctuations scale with the KLS critical exponents. However, if both temperatures are set well above the critical temperature, the particle density fluctuations scale according to the totally asymmetric exclusion process (TASEP). We have also measured the entropy production rate in both subsystems; it displays intriguing algebraic decay in the critical region, while it saturates quickly at a small but non-zero level in the hotter region. We have also considered another possible choice of the hopping rates across the temperature interfaces that explicitly breaks particle-hole symmetry. In that case the boundary rates induce a net particle flux across the interfaces that displays power-law behavior, until ultimately the particle exclusion constraints generate a clogging transition to an inert state.

中文翻译：

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Katz-Lebowitz-Spohn 驱动的晶格气体中的平行温度界面

我们在二维中探索了 Katz-Lebowitz-Spohn (KLS) 驱动的晶格气体的变体，其中晶格被分成两个区域，这些区域与具有不同温度的热浴耦合。温度边界平行于外部粒子驱动。如果界面处的跳跃率满足粒子-空穴对称性，它们之间的电流差异会生成类似于涡流片的矢量流图。我们研究了两个温度区域中粒子密度波动的有限尺寸缩放，并观察到它受各自温度值的控制。如果较冷的子系统保持在 KLS 临界温度，而较热的子系统的温度设置得更高，则界面电流会大大抑制两个区域之间的粒子交换。由于随后有效的子系统解耦，临界区域内持续存在强烈波动，因此粒子密度波动与 KLS 临界指数成比例。然而，如果两个温度都设置得远高于临界温度，则粒子密度波动会根据完全不对称排除过程 (TASEP) 进行缩放。我们还测量了两个子系统中的熵产生率；它在临界区域显示出有趣的代数衰减，而在较热的区域中它在一个很小但非零的水平上迅速饱和。我们还考虑了另一种可能的跨温度界面跳跃率的选择，它明确地破坏了粒子 - 孔的对称性。在这种情况下，边界速率会导致界面上的净粒子通量显示幂律行为，