Recent content by hlpmostafa

We do use ##u_{nk}## for calculating the Berry phase and it is true that ##u_{k}(x) = e^{iGx}u_{k+G}(x)##, but I think all that matters for the definition of the Brillouin zone as a torus is that ##\psi_k = \psi_{k+G}##.

you know we have electric field on the surface of the earth.if this external electric field had an effect on light trajectory...