A lithium niobate plate 2.0 mm thick is cut with its optic axis at to the face normal

PHYSICS · Multi-part · Fermi University Physics · Optics & Photonics · Polarisation and anisotropic media · Polarisation and anisotropic media

What an Instrument Can See, Ch Anisotropic media: the dielectric tensor and the index ellipsoid

Problem

A lithium niobate plate 2.0 mm thick is cut with its optic axis at

30^\circ

to the face normal. Lithium niobate is negative uniaxial with

n_o = 2.286

and

n_e = 2.200

at 589 nm. A plane wave enters normally, so its wave vector inside the crystal makes

30^\circ

with the optic axis. ((a)) Find the walk-off angle

\rho_w

of the extraordinary wave. ((b)) Find the lateral displacement between the ordinary and extraordinary beams on leaving the plate.