Infrared fibers offer a versatile approach to guiding and manipulating light in the infrared spectrum, which is becoming increasingly more prominent in a variety of scientific disciplines and technological applications. Despite well-established efforts on the fabrication of infrared fibers over the past decades, a number of remarkable breakthroughs have recently rejuvenated the field ? just as related areas in infrared optical technology are reaching maturation. In this review, we describe both the history and recent developments in the design and fabrication of infrared fibers including infrared glass and singlecrystal fibers, multimaterial fibers, and fibers that exploit the transparency window of traditional crystalline semiconductors. This interdisciplinary review will be of interest to researchers in optics and photonics, materials science, and electrical engineering.
