Laser Elsewhere, in the U.S., Schawlow and Townes had agreed to an open-resonator laser design – apparently unaware of Prokhorov's publications and Gould's unpublished laser work. At a conference in 1959, Gordon Gould published the term LASER in the paper "The LASER, Light Amplification by Stimulated Emission of Radiation". Gould's linguistic intention was using the "-aser" word particle as a suffix – to accurately denote the spectrum of the light emitted by the LASER device; thus x-rays: "xaser", ultraviolet: "uvaser", et cetera; none established itself as a discrete term, although "raser" was briefly popular for denoting radio-frequency-emitting devices. Gould's notes included
Raman amplification Raman amplification Raman amplification is based on the stimulated Raman scattering (SRS) phenomenon, when a lower frequency 'signal' photon induces the inelastic scattering of a higher-frequency 'pump' photon in an optical medium in the nonlinear regime. As a result of this, another 'signal' photon is produced, with the surplus energy resonantly passed to the vibrational states of the medium. This process, as with other stimulated emission processes, allows all-optical amplification. Optical fiber is today mostly used as the nonlinear medium for SRS, for telecom purposes; in this case it is characterized by a resonance frequency downshift of ~11 THz (corresponding