Dielectric materials as photonic crystal and formulation of lamb shift using anisotropic model

Dielectric studies with characteristics of a photonic crystal and a new expression of Lamb Shift including spatial average of dielectric constant for the material and its surrounding for odd parity of 2p/sub 1/2/ state of hydrogen for photon-atom interaction as a function of relative dispersion frequency, refractive index contrast and propagation vector using quadratic fluctuations and randomness in an anisotropic model of Brillouin Zone (BZ) for p-polarization are reported. The anomalous Lamb shift in 2p/sub 1/2/ level is significantly more than that obtained by using isotropic model which indicates that introducing anisotropic behaviour of BZ is important.