KNa2La2(BO3)3: a shortite-type lanthanide borate exhibiting strong nonlinear optical activity induced by isolated [BO3] triangles and distorted [LaO9] polyhedra

A new rare earth borate KNa 2 La 2 (BO 3 ) 3 was experimentally fabricated. It fully achieved the coexistence of strong phase-matching SHG response (2.6 × KDP), a short UV cut-off edge (212 nm) and a wide band gap (5.3 eV).