Gopalakrishnan Sarang, McCulloch Ewan, Vasseur Romain
Department of Electrical and Computer Engineering, Princeton University, Princeton, NJ 08544.
Department of Physics, University of Massachusetts, Amherst, MA 01003.
Proc Natl Acad Sci U S A. 2024 Dec 10;121(50):e2403327121. doi: 10.1073/pnas.2403327121. Epub 2024 Dec 4.
Dirac fluids-interacting systems obeying particle-hole symmetry and Lorentz invariance-are among the simplest hydrodynamic systems; they have also been studied as effective descriptions of transport in strongly interacting Dirac semimetals. Direct experimental signatures of the Dirac fluid are elusive, as its charge transport is diffusive as in conventional metals. In this paper, we point out a striking consequence of fluctuating relativistic hydrodynamics: The full counting statistics (FCS) of charge transport is highly non-Gaussian. We predict the exact asymptotic form of the FCS, which generalizes a result previously derived for certain interacting integrable systems. A consequence is that, starting from quasi-one-dimensional nonequilibrium initial conditions, charge noise in the hydrodynamic regime is parametrically enhanced relative to that in conventional diffusive metals.
狄拉克流体相互作用系统服从粒子-空穴对称性和洛伦兹不变性，是最简单的流体动力学系统之一；它们也被作为强相互作用狄拉克半金属中输运的有效描述进行了研究。狄拉克流体的直接实验特征难以捉摸，因为其电荷输运与传统金属一样是扩散性的。在本文中，我们指出了波动相对论流体动力学的一个显著结果：电荷输运的全计数统计（FCS）是高度非高斯的。我们预测了FCS的精确渐近形式，它推广了先前为某些相互作用可积系统得出的结果。一个结果是，从准一维非平衡初始条件出发，流体动力学区域中的电荷噪声相对于传统扩散金属中的电荷噪声会以参数方式增强。
