论文标题
什么是量子冲击波？
What is a quantum shock wave?
论文作者
论文摘要
冲击波是物质远程平衡行为的例子。它们本质上是普遍存在的，但是尚不清楚其形成背后的基本微观机制。在这里，我们研究了一维bose气体中色散量子冲击波的动力学，并表明从局部密度凸起形成的振荡性序列膨胀到均匀的背景是量子机械自我干扰的结果。振荡的幅度，即干扰对比，随着气体温度的升高和由于相位相干长度的降低而降低。此外，我们表明，由于在平均值周围的干扰条纹位置，真空和热波动可以显着清除平均场进近的干扰对比度。
Shock waves are examples of the far-from-equilibrium behaviour of matter; they are ubiquitous in nature, yet the underlying microscopic mechanisms behind their formation are not well understood. Here, we study the dynamics of dispersive quantum shock waves in a one-dimensional Bose gas, and show that the oscillatory train forming from a local density bump expanding into a uniform background is a result of quantum mechanical self-interference. The amplitude of oscillations, i.e., the interference contrast, decreases with the increase of both the temperature of the gas and the interaction strength due to the reduced phase coherence length. Furthermore, we show that vacuum and thermal fluctuations can significantly wash out the interference contrast, seen in the mean-field approaches, due to shot-to-shot fluctuations in the position of interference fringes around the mean.
