Enhanced near-infrared femtosecond nonlinear optical properties in zinc borate glasses activated with Er2O3

Effect of Nd2O3 Concentration on Crystallization Mechanism and Third-Order Optical Nonlinearity of Lanthanide-Titanium-Tellurite Glass and Glass-Ceramics

“…Hence, the observed optical nonlinearity in the currently studied matrices is due to a two-photon absorption (2PA) process at 800 nm and a three-photon absorption (3PA) process at longer wavelengths (1000 and 1200 nm). Further, the NLO coefficients of 2PA and 3PA (α 2 and α 3 , respectively) have been estimated from the experimentally observed OA Z -scan data using eq by considering the values of n = 2 and n = 3, respectively ,, italicT OA ( n PA ) = 1 false[ 1 + ( n − 1 ) α n L normale normalf normalf false( I 00 / ( 1 + ( Z / Z 0 ) 2 ) false) n − 1 false] 1 / n − 1 where n = order of absorption process, α n = multiphonon absorption coefficient, I 00 = input laser irradiation intensity, L eff = effective path length travel by laser beam within the sample, Z = sample position, and Z 0 = Rayleigh range. The OA plots of all the matrices at 800 nm using the value n = 2 are shown in Figure a–c.…”

“…The CA Z -scan profiles (Figure d–f) demonstrate a prefocal dip followed by a postfocal peak, which is the signature pattern of positive nonlinear refraction. The corresponding data points were fitted with eq followed by eq to estimate the nonlinear refractive index ( n 2 ) ,, italicT CA = 1 + 4 normalΔ ϕ 0 ( Z / Z 0 ) [ 1 + ( Z / Z 0 ) 2 ] [ 9 + ( Z / Z 0 ) 2 ] italicn 2 .25em ( m 2 / W ) = | Δ ϕ 0 | λ 2 π I 00 L normale normalf normalf where Δϕ 0 = phase difference of the laser radiation and λ = excitation wavelength.…”

“…The NLO properties of a glass can also be tuned through ceramization. 13,14 Nonetheless, very few articles are available on the NLO properties of nano/microcrystallite embedded glassceramics (GCs). 14−17 Zhou et al have reported the optical limiting performance of transparent lithium-niobate 15 and borotitanate 17 GCs.…”

“…The NLO properties of a glass can also be tuned through ceramization. , Nonetheless, very few articles are available on the NLO properties of nano/microcrystallite embedded glass-ceramics (GCs). − Zhou et al have reported the optical limiting performance of transparent lithium-niobate and boro-titanate GCs. The authors have shown that lithium-niobate GCs exhibit a much lower limiting threshold of ∼200 GW/cm 2 than its parent glass (270 GW/cm 2 ) due to the decrease in bandgap .…”