Excellent nonlinear absorption properties of 2D germanium nanosheets in the infrared band

Passively mode-locked Er-doped fiber laser with single and double wavelength pulses based on germanene saturable absorber

“…Figure 2(a) represents the Raman spectrum of the Ge crystal, from which it can be seen that there is only one wave peak at 299.1 cm −1 . This indicates that our prepared Ge SA is consistent with what has been previously reported [53]. From figure 2(b), we can obtain that the transmittance increases with increasing wavelength.…”

2D Ta4AlC3 and Ta4C3 nanosheets with excellent ultraviolet optical limiting behavior for laser protection

“…The TPA cross-sections at 1064 nm and 532 nm excitation wavelengths are 0.81 ± 0.02 × 10 −45 and 2.51 ± 0.09 × 10 −45 cm 4 s, respectively, which are smaller than those of Ta 4 AlC 3 (one order of magnitude larger) and Ta 4 C 3 , and 4.29 ± 0.05 × 10 −45 cm 4 s at 355 nm excitation wavelength is two orders of magnitude smaller than that of Ta 4 AlC 3 and one order of magnitude smaller than that of Ta 4 C 3 , further illustrating the advantages of Ta 4 AlC 3 and Ta 4 C 3 as OL materials. In addition, the smaller I s compared to 2D Ge 45 and MoS 2 46 again demonstrates the superior NLA properties of Ta 4 AlC 3 and Ta 4 C 3 . The results indicate the excellent NLA properties of Ta 4 AlC 3 and Ta 4 C 3 , especially the strong OL behavior in the UV region, which have potential applications in the field of laser protection.…”