Geometric Phase From Dielectric Matrix
  The dielectric property $(2\times2)$ of the anisotropic optical medium is found out considering the polarized photon as two component spinor of spherical harmonics.The Geometric Phase of single polarized photon has been evaluated in two ways. The phase two-form of the dielectric matrix through a twist and the Pancharatnam phase (GP) through the change of angular momentum of the incident polarized photon over a closed triangular path on the extended Poincare sphere. The helicity in connection with the spin angular momentum of the chiral photon plays the key role in developing these phase holonomies. 
Dipti Banerjee