by electron-electron interactions, rather than the electron-phonon interaction that is responsible for conventional BCS superconductivity.
Nokia adopted Phonon for multimedia use in Qt 4.4 and are developing backends for Gstreamer, Windows and OS X in the KDE SVN repository under the LGPL.
However, as the magnitude of the Seebeck coefficient increases with phonon drag, it may be beneficial in a thermoelectric material for direct energy conversion applications.
Inelastic neutron scattering measurements can determine the dispersion curve for magnons just as they can for phonons. Important inelastic neutron scattering facilities are present at the ISIS neutron source in Oxfordshire, UK, the Institut Laue-Langevin in Grenoble, France, the High Flux Isotope Reactor at Oak Ridge National Laboratory in Tennessee, USA, and at the National Institute of Standards and Technology in Maryland, USA.
The shape of the zero-phonon line is Lorentzian with a width determined by the excited state lifetime T10 according to the Heisenberg uncertainty principle.