Mid-infrared laser chaos lidar

Chaos lidars detect targets through the cross-correlation between the back-scattered chaos signal from the target and the local reference signal. Chaos lidars have excellent anti-jamming and anti-interference capabilities, owing to the random nature of chaotic oscillations. However, most chaos lidars operate in the near-infrared spectral regime, with significant atmospheric attenuation. Here we show a mid-infrared chaos lidar which is suitable for long-reach ranging and imaging applications within the atmosphere's low-loss transmission window. The proof-of-concept mid-infrared chaos lidar utilizes an interband cascade laser with optical feedback as the laser chaos source. Experimental results reveal that the chaos lidar achieves an accuracy better than 0.9 cm and a precision better than 0.3 cm for ranging distances up to 300 cm. In addition, it is found that a minimum signal-to-noise ratio of only 1 dB is required to sustain both sub-cm accuracy and sub-cm precision. This work paves the way for developing remote chaos lidar systems in the mid-infrared spectral regime.