All-fiber devices compatible with the mid-infrared

The mid-infrared spectrum of light $(2-20 \mu \mathrm{m})$ is a topic of technological excitement and growing research activity. Chemical substances exhibit vibrational and rotational absorption bands in the mid-IR, and the unique signature left by the absorption of light by these fundamental bands provides a universal means for their identification and quantification. This has applications in medicine and biology, industrial processes, environment monitoring, defense, quantum optics, and imaging.