title: Dispersion relations of refractive indices suitable for KBe2BO3F2crystal deep-ultraviolet applications.
abstract: KBe2BO3F2(KBBF) is the only nonlinear optical crystal available to generate deep-ultraviolet (DUV) laser output by direct harmonic generation. High-precision refractive indices, including in the DUV region, were measured, and starting from a double resonance model of polarizability, new dispersion relations of the refractive indices were deduced from the measured data. The predicted phase matching angles for second-harmonic generation down to 165 nm from the new relations agree well with the previous reported values. Moreover, the new dispersion relations show superior results in an even shorter wavelength range, giving perfectly calculated phase matching angles for fifth-harmonic generation down to as short as 149.8 nm.
authors.forename: Rukang
authors.initials: R
authors.lastname: Li
authors.forename: Lirong
authors.initials: L
authors.lastname: Wang
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Wang
authors.forename: Guiling
authors.initials: G
authors.lastname: Wang
authors.forename: Chuangtian
authors.initials: C
authors.lastname: Chen