Dislocation roughening in quantum crystals
Department of Engineering Science and Physics, CSI, CUNY - Staten Island, NY 10314, USA
2 Department of Physics, CCNY CUNY - New York, NY 10031, USA
Corresponding author: Anatoly.Kuklov@csi.cuny.edu
Accepted: 3 February 2010
We address generic behavior of quantum dislocations in almost ideal crystals. It is proven that the combination of arbitrary small Peierls potential and Coulomb-type elastic interaction between dislocation kinks prevents quantum roughening of dislocations. Thermally created kinks induce classical roughening which leads to softening of crystal shear modulus at temperatures comparable to the kink energy. This effect is discussed in the context of the shear modulus softening observed by Day & Beamish in solid 4He.
PACS: 67.80.bd – Superfluidity in solid 4He, supersolid 4He / 67.80.-s – Quantum solids / 05.30.Jp – Boson systems
© EPLA, 2010