- Phason
Phason is a
quasiparticle existing inquasicrystal s due to their specific, quasiperiodic lattice structure. Similar tophonon , phason is associated with atomic motion. However, whereas phonons are related to "translation" of atoms, phasons are associated with atomic "rearrangements". As a result of these rearrangements, waves, describing the position of atoms in crystal, change phase, thus the term "phason".The hydrodynamic theory of the quasicrystals predicts that the conventional (phonon) strain relaxes rapidly. On the contrary, relaxation of the phason strain is diffusive and is much slower. ["Hydrodynamics of icosahedral quasicrystals" [http://link.aps.org/abstract/PRB/v32/p7444 Phys. Rev. B 32, 7444–7452 (1985)] ] Therefore, metastable quasicrystals grown by rapid quenching from the melt exhibit built-in phason strain ["Icosahedral clusters, icosaheral order and stability of quasicrystals—a view of metallurgy" [http://dx.doi.org/10.1088/1468-6996/9/1/013008 Sci. Technol. Adv. Mater. 9 No 1 (2008) 013008] : "free-download review"] associated with shifts and broadenings of X-ray and
electron diffraction peaks. ["Distortion and Peak Broadening in Diffraction Patterns" [http://link.aps.org/abstract/PRL/v57/p1440 Phys. Rev. Lett. 57, 1440–1443 (1986)] ]References
Books
*P.J. Steinhardt and S. Ostlund The Physics of Quasicrystals (Singapore: World Scientific, 1987)
*D. P. DiVincenzo and P. J. Steinhardt, eds. "Quasicrystals: The State of the Art". Directions in Condensed Matter Physics, Vol 11. ISBN 981-02-0522-8, 1991.
*M. Senechal," Quasicrystals and Geometry", Cambridge University Press, 1995.
*J. Patera," Quasicrystals and Discrete Geometry ", 1998.
*E. Belin-Ferre et al., eds. "Quasicrystals", 2000.
*Hans-Rainer Trebin ed., "Quasicrystals: Structure and Physical Properties " 2003.ee also
*
quasicrystal
*quasiparticles
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