title: Efficient mid-IR spectral generation via spontaneous fifth-order cascaded-Raman amplification in silica fibers.
abstract: Spontaneous cascaded Raman amplification is demonstrated as a practical and efficient means of power transfer from telecommunications wavelengths to mid-IR wavelength bands through use of conventional silica fibers and amplifiers. We show that silica fibers possessing normal dispersion over all near-IR and mid-IR wavelengths can facilitate 37% and 16% efficient Raman power conversion from 1.53 microm to 2.15 and 2.41 microm wavelength bands, respectively, using nanosecond pulses from an all-fiber laser source. In contrast to supercontinuum-based techniques for long-wavelength generation, the high levels of Raman gain generated at these wavelength bands could produce useful optical amplification necessary for the development of numerous mid-IR laser sources.
authors.affiliation: Research Laboratory of Electronics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA. rakich@alum.mit.edu
authors.forename: Peter T
authors.initials: PT
authors.lastname: Rakich
authors.forename: Yoel
authors.initials: Y
authors.lastname: Fink
authors.forename: Marin
authors.initials: M
authors.lastname: Soljacić