Coherent Random Fiber Laser-Enabled Super-Resolution Spectroscopy

Inspired by single-molecule localizationmicroscopy,super-resolutionspectroscopy has been achieved by sparse sampling in the spectraldomain, where a light source capable of randomly emitting sparse peaksplays a crucial role. Due to the intrinsic feedback mechanism of disorderedlight scattering, random lasers can provide the desired emission characteristicsthat facilitate reconstructing the detailed spectral profiles of samples.Here, we propose an all-fiber-configured coherent random laser forspectral measurement to break the instrumental response limitationof spectral detection systems. The laser remains in a chaotic regimeand exhibits self-modulating spectral behavior by introducing an elaboratelydesigned spectral tailoring element inside the cavity. The statisticalnumber and distribution of the random peaks over the emission spectrumcan be manipulated by adjusting the pump power. In addition, the laserexhibits several attractive features, such as low pumping threshold,narrow-line-width lasing modes, flexible operating wavelength range,high optical signal-to-noise ratio, and easy compatibility with opticalfiber systems. Using a low-resolution spectrograph, we experimentallydemonstrate super-resolution spectrum reconstruction, obtaining aspectral enhancement of around 3.3. This work provides a powerfulillumination source and realization method for high-resolution spectroscopy,which is an essential tool for future optical information applications.