Rutile ( ) is a tetragonal

PHYSICS · Multi-part · Fermi University Physics · Optics & Photonics · Condensed Matter, Materials & Soft Matter · Polarisation and anisotropic media

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

Problem

Rutile (

\mathrm{TiO_2}

) is a tetragonal, uniaxial crystal. At 590 nm its principal indices are

n_o = 2.616

and

n_e = 2.903

(positive uniaxial:

n_e > n_o

). The crystal is transparent and shows no optical activity at this wavelength. ((a)) Write the dielectric tensor

\epsilon_{ij}

in the crystal's principal axes, with the optic axis along

z

. ((b)) A plane wave travels at

40^\circ

to the optic axis. Find the index

n(40^\circ)

of the extraordinary eigenmode.