论文标题
在血浆Wakefield中真空双折射的签名增强
Enhanced signature of vacuum birefringence in a plasma wakefield
论文作者
论文摘要
真空双向（VB）是量子电动力学（QED）中预测的基本现象。但是，由于信号的较小，基于传统的磁铁和极其激烈的激光驱动的检测方法仍然非常具有挑战性。这是因为在第一种情况下，相互作用长度很大，但场是有限的，在第二种情况下，反之亦然。我们提出了一种在等离子体气泡Wakefield中生成和检测VB的方法，该方法结合了这两个优势，可沿较大的相互作用长度提供大型田地。两极化的$γ$ - 光束被认为是沿着毫米的繁殖距离探测韦克菲尔德到等离子体气泡中的几厘米。我们通过血浆粒子中的模拟发现，在Stokes参数方面，Vb信号可以达到$ 10^{ - 5} $（$ 10^{ - 3} $ - $ 10^{ - 2} $），用于数十MEV（GEV）探针光子， （$ 10^{20} $ - $ 10^{21}〜\ Mathrm {w/cm^2} $）。血浆电子的主要噪声来源特别是通过选择$γ$ - 光子极化和血浆密度的适当调节。所提出的方法代表了通过激光 - 血浆相互作用对VB进行实验观察的一种有吸引力的替代方法。
Vacuum birefringence (VB) is a basic phenomenon predicted in quantum electrodynamics (QED). However, due to the smallness of the signal, conventional magnet-based and extremely intense laser-driven detection methods are still very challenging. This is because in the first case the interaction length is large but the field is limited, and vice versa in the second case. We put forward a method to generate and detect VB in a plasma bubble wakefield, which combines both advantages, providing large fields along large interaction lengths. A polarized $γ$-photon beam is considered to probe the wakefield along a propagation distance of millimeters to centimeters in the plasma bubble. We find via plasma particle-in-cell simulations that the VB signal in terms of Stokes parameters can reach about $ 10^{-5}$ ($10^{-3}$-$10^{-2}$) for tens of MeV (GeV) probe photons with moderately intense lasers ($10^{20}$-$10^{21}~\mathrm{W/cm^2}$). The main source of noise from plasma electrons is mitigated, in particular, by a choice of $γ$-photon polarization and by proper modulation of the plasma density. The proposed method represents an attractive alternative for the experimental observation of VB via laser-plasma interaction.
