论文标题
沃尔科夫繁殖器的准经典表示和平面波中的t图
Quasiclassical representation of the Volkov propagator and the tadpole diagram in a plane wave
论文作者
论文摘要
与所谓的Volkov状态相对应的任意平面波的存在，狄拉克方程的解提供了强场QED的巨大见解。在[Phys。已经找到了沃尔科夫国家的新的“完全准经典”表示，这与文献中已知的一种相当，但更透明地显示了平面波波场中电子的量子动力学的准经典性质。在这里，我们通过使用沃尔科夫态的完全准准经典形式来得出传播剂的相应表达。发现的表达允许沃尔科夫状态的完全准确的表达，可以通过仅操作2 by-2而不是4 by-4 dirac矩阵来计算强场在强场中的概率，如通常的方法。此外，除了指数函数以电子在平面波中的经典作用为特定的函数外，完全准准经典的Volkov繁殖器仅取决于平面波中的电子动力学四弹药，这是一个规范的数量。最后，我们还计算了从沃尔科夫繁殖器开始的平面波中的一环t图，我们发现在重新归一化后，它消失了。
The solution of the Dirac equation in the presence of an arbitrary plane wave, corresponding to the so-called Volkov states, has provided an enormous insight in strong-field QED. In [Phys. Rev. A \textbf{103}, 076011 (2021)] a new "fully quasiclassical" representation of the Volkov states has been found, which is equivalent to the one known in the literature but which more transparently shows the quasiclassical nature of the quantum dynamics of an electron in a plane-wave field. Here, we derive the corresponding expression of the propagator by constructing it using the fully quasiclassical form of the Volkov states. The found expression allows one, together with the fully quasiclassical expression of the Volkov states, to compute probabilities in strong-field QED in an intense plane wave by manipulating only 2-by-2 rather than 4-by-4 Dirac matrices as in the usual approach. Moreover, apart from the exponential functions featuring the classical action of an electron in a plane wave, the fully quasiclassical Volkov propagator depends only on the electron kinetic four-momentum in the plane wave, which is a gauge-invariant quantity. Finally, we also compute the one-loop tadpole diagram in a plane wave starting from the Volkov propagator and we find that after renormalization it identically vanishes.
