论文标题
重离子碰撞中的自旋大厅效应
Spin Hall effect in heavy ion collisions
论文作者
论文摘要
自旋大厅效应（SHE）是由于电场引起的自旋电流的产生，并且已经在各种材料中观察到。类似的自旋大厅电流可以通过化学势和温度梯度诱导，它们都存在于重合离子碰撞中产生的热和密集的核物质中。在这封信中，我们研究了实验检测旋转厅电流的观点。我们建议测量“定向旋转流”，这是中央碰撞的局部旋转极化的第一个傅立叶系数，$λ$（$ \barλ$）超子，以探测旋转霍尔电流。为了量化诱导的自旋电流，我们使用热场理论评估相关的运输系数。我们基准在两个代表性的碰撞能量上基于引起的“定向旋转流”的大小，即$ \ sqrt {s} _ {nn} = 200〜 {\ rm gev} $和$ \ sqrt {s} _ {s} _ {nn} = 19.6〜 { 处方。在两个光束能量上，由此产生的“定向旋转流”范围从$ 10^{ - 4} $到$ 10^{ - 3} $，并且对速度非常敏感。
Spin Hall effect (SHE) is the generation of spin current due to an electric field, and has been observed in a variety of materials. The analogous spin Hall current can be induced by chemical potential and temperature gradient, both of which are present in hot and dense nuclear matter created in heavy-ion collisions. In this letter, we investigate the perspective of detecting spin Hall current experimentally. We propose to measure "directed spin flow", the first Fourier coefficients of local spin polarization of $Λ$ ($\barΛ$) hyperon, at central collisions to probe spin Hall current. To quantify induced spin current, we evaluate relevant transport coefficients using thermal field theory. We benchmark the magnitude of the induced "directed spin flow" at two representatively collisions energies, namely $\sqrt{s}_{NN}=200~{\rm GeV}$ and $\sqrt{s}_{NN}=19.6~{\rm GeV}$, by employing a phenomenologically motivated freeze-out prescription. At both beam energies, the resulting "directed spin flow" ranges from $10^{-4}$ to $10^{-3}$, and is very sensitive to the rapidity.
