William Atkins
Tuesday, 08 September 2009 18:40
Science -
Energy
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The first-ever phonon laser—a device that uses phonons, or the smallest discrete (quantized) unit of vibrational energy—has been created by German and U.S. scientists. The phonon laser uses amplified sound instead of light.
Scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) and the California Institute of Technology (Pasadena, California, U.S.A.) used a process called stimulated emission to create the first-of-its-kind phonon laser.
Like an optical laser--an acronym for
Light Amplification by Stimulated Emission of Radiation--which uses emitted light, the “sound” laser, or phonon laser, is called a “saser"--an acronym for
Sound Amplification by Stimulated Emission of Radiation.
The saser, also called an acoustic laser, uses a highly coherent beam of ultrasound.
Phonons are important in solid-state physics because they produce many properties inherent in solids.
For instance, the thermal (heat) and electrical conductivities of solids are provided in large part by phonons. And, sounds heard in solids are also present because of phonons, which is why phonons mean “voice” in Latin.
The summary of their work is published online in the journal
Nature Physics (Publication 16. August 09, DOI: 10.1038/ NPHYS1367).
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