Relativistic spinor equation of photon
  In this paper, we have proposed the spiron equation of free and non-free photon, and give the spin operator and spin wave function of photon. We calculate the helicity of photon and prove there are left-handed and right-handed photon. By the spiron equation of non-free photon, we can study the quantum property of photon in medium, which can be used in quantum optics, photonic crystals and so on. 
Xiang-Yao Wu, Hong Li, Xiao-Jing Liu, Si-Qi Zhang, Ji Ma, Guang-Huai   Wang, Hai-Xin Gao, Heng-Mei Li, Hong-Chun Yuan
physics.gen-ph quant-ph