Oxide nonlinear crystals: optical properties and phase-matching for terahertz wave generation O.I. Potaturkin, V.D. Antsygin, A.A. Mamrashev, N.A. Nikolaev, Yu.M. Andreev, G.V. Lanskii, V.A. Svetlichnyi and K.A. Kokh EPJ Web Conf., 195 (2018) 06012 Published online: 23 November 2018 DOI: 10.1051/epjconf/201819506012