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and Townes had agreed to an open-resonator laser design – apparently unaware of Prokhorov's publications and Gould's unpublished laser work.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
Sound amplification by stimulated emission of radiation operates at about 440 GHz, while the Caltech device operates in the megahertz range. According to a member of the Nottingham group, the two approaches are complementary and it should be possible to use one device or the other to create coherent phonons at any frequency in the megahertz to terahertz range. A significant result rises from the operating frequency of these devices. The differences between the two devices suggest that SASERs could be made to operate over a wide range of frequencies. Work on the SASER continues at the University of Nottingham, the "Lashkarev Institute of Semiconductor Physics" at