Dielectric properties of BiB3O6 crystal in the sub-THz range

We present the thorough studies of dielectric properties of BiB
3
O
6
(BIBO) crystal in the sub-THz range. We observe a large birefringence Δn = nZ −nX = 1.5 and the values of absorption coefficients of all three axes to be less than 0.5 cm
⁻¹
. The difference from visible range in angle ϕ between the axes z and X is found to be more than 6°. The simulated phase-matching curves show the optimal value of the angle θ to be around 25.5°±1° for an efficient millimeter-wave generation under the pump of 1064 nm laser radiation.