1. An electric field is applied to a hexagonal 222 crystal along the y-axis. The r-mutrix of the crystal is given by 0 0 0 0. 0. 0. 00 0 0 I'52 Assuming that the crystal starts out non-birefringent with ny ly = n = lg- a. What are the new principal indices? b. What are the new principal axes? c. If the electric field applied to the crystal is modulated, what should the incident polarization direction to make it a phase modulator? (Assume propugation along the y-axis).