Acousto-Optic Tunable Filter Enables Flexible Multi-Wavelength Lasers

Multi-wavelength lasers have become increasingly popular in recent years due to their broad range of applications in various fields. In a recent study, researchers demonstrated a multi-wavelength random fiber laser with the ability to customize its spectra through the use of an acousto–optic tunable filter. This filter allowed for tuning the operating wavelength from 1114.5 to 1132.5 nm, with a maximum output power of 5.55 W and the potential for a maximum of five spectral channels.

The study also examined the effects of gain competition and the interaction between Raman gain and insertion loss. By radiating specific radio frequency signals to the acousto–optic tunable filter, the researchers were able to order the output spectra. This opens up the possibility for more flexible and efficient shape spectrum generation.

The results showed that the central wavelength of the multi-wavelength laser could be tuned within a range of 1114.5-1132.5 nm, with the potential for up to five spectral channels. The linewidth of the laser could also be widened to 4.5 nm through the use of the designed radio frequency signals. The optimized loss of the filter compensated for the gain spectrum, resulting in equal amplitude multi-wavelength outputs. With further adjustments, the researchers were able to achieve a customized spectral envelope.

This spectrum-customizable multi-wavelength random fiber laser has the potential to broaden the tuning range of tunable fiber lasers and make multi-wavelength lasers more practical for use in areas such as sensing, telecommunications, and precise spectroscopy.

In conclusion, the researchers successfully demonstrated a multi-wavelength random fiber laser with customizable spectra enabled by an acousto–optic tunable filter. The laser showed potential for use in a variety of fields, and the results of this study could serve as a reference for future developments in multi-wavelength laser technology.