Research Information System
Ukrainian Journal of Physics, vol.71, no.4, pp.275-282, 2026 (ESCI, Scopus)
We present a novel single-beam refraction-modulation Z-scan technique that combines elements of the standard Z-scan and loss-modulation methods to enable sensitive measurement of third-order refractive nonlinearities in the closed-aperture configuration. Compared with the original Z-scan technique, the proposed method provides an almost background-free signal. An analytical expression relating the nonlinear refractive index n2 to the powers of the incident beam and the transmitted beam components at the first and second modulation harmonics is derived and experimentally verified using SiO2 and LiF samples.