Sound amplification by stimulated emission of radiation the axes of the mirrors, it is possible for photons to repeat multiple reflections and force more and more photons to follow them producing an avalanche effect. The number of photons of this coherent laser beam increases and competes the number of photons perished due to losses. The basic necessary condition for the generation of a laser radiation is the population inversion, which can be achieved either by exciting atoms and inducing percussion or by external radiation absorption. A SASER device mimics this procedure using a source-pump to induce a sound beam of phonons. This sound beam propagates not in
A Sound Garden A Sound Garden A Sound Garden is one of six outdoor public art works on the National Oceanic and Atmospheric Administration (NOAA) campus that lies adjacent to the Warren G. Magnuson Park on the northwestern shore of Lake Washington in Seattle, Washington. The Seattle Arts Commission guided the jury selection headed by Sadao James Hilario, Engineer-in-charge of the GSA Art in Architecture Program for the NOAA Project, and the jury chose five artists from a pool of more than 250. Designed and built by sculptor Douglas Hollis from 1982–83, "A Sound Garden" is a sculptural group composed of 12 21