The saturable absorption behaviour associated with chalcogenide thin films has been investigated and optimized using Z-Scan Technique. Huge saturable absorption responses (of the order of 10^-7 m/W) ...were observed for the Bismuth Selenide thin films, which depend on material characteristics and the laser parameters. An approach in which the application of the saturable absorber thin films for super-resolved laser inscriptions has been discussed and a theoretical analysis of the super-resolution efficiency of the thin films has been made.
Topological insulators, such as the Bi
2
Se
3
material, exhibit significant optical nonlinearities. This work investigates the impact of the pulse duration on the nonlinear optical responses of Bi
2
...Se
3
layers. Scanning electron microscopy studies have been performed to reveal the crystalline structure of the samples. The nonlinear optical performance has been investigated for a wide range of pulse durations, from 400 fs to 10 ps, using 1030 nm laser excitation. The nonlinear absorption coefficients recorded in this study range from -1.45 x10
−7
m/W to -4.86 x10
−7
m/W. The influence of two different mechanisms on optical nonlinearities was observed and discussed. Identical experimental conditions have been employed throughout the studies allowing a direct comparison of the results.
Topological insulators, such as the Bi2Se3 material, exhibit significant optical nonlinearities. This work investigates the impact of the pulse duration on the nonlinear optical responses of Bi2Se3 ...layers. Scanning electron microscopy studies have been performed to reveal the crystalline structure of the samples. The nonlinear optical performance has been investigated for a wide range of pulse durations, from 400 fs to 10 ps, using 1030 nm laser excitation. The nonlinear absorption coefficients recorded in this study range from-1.45 x10 −7 m/W to-4.86 x10 −7 m/W. The influence of two different mechanisms on optical nonlinearities was observed and discussed. Identical experimental conditions have been employed throughout the studies allowing a direct comparison of the results.
The thickness-dependent saturable absorption behaviour of atomically thin bismuth selenide films has been optimized using 515 nm and 1030 nm laser excitation wavelengths. The studies have been ...performed by the Z-scan technique employing 400 fs laser pulses emitted by a fiber laser at a repetition rate of 100 Hz. The obtained results allowed the determination of the nonlinear optical parameters as a function of the film thickness. Additional studies have been carried out in order to determine the third-order optical nonlinearities as a function of the annealing temperature. The samples have also been studied by spectrophotometry, electron microscopy and X-ray diffraction, which allowed a deeper knowledge of the optical properties, as well as the crystalline structure of the Bi2Se3 material.
•Giant ultrafast nonlinear optical responses have been recorded and compared with the literature.•Precise optimization of both the 2D material and excitation parameters for maximizing the optical nonlinearities.•The 2D materials are nonlinear optically active in the visible (515 nm) and infrared (1030 nm) parts of the spectrum.•The topological insulators were characterized by X-ray diffraction, scanning electron microscopy and spectrophotometry.
