Volume 87, Number 6, September 2009
Article Number 66001
Number of page(s) 4
Section Condensed Matter: Structural, Mechanical and Thermal Properties
Published online 28 September 2009
EPL, 87 (2009) 66001
DOI: 10.1209/0295-5075/87/66001

Grain boundary roughening transitions

S. T. Chui

Bartol Research Institute and Deptartment of Physics and Astronomy, University of Delaware Newark, DE 19716, USA

received 4 August 2009; accepted in final form 3 September 2009; published September 2009
published online 28 September 2009

We consider the roughening of small-angle grain boundaries consisting of arrays of dislocations and found two transitions, corresponding to fluctuations of the dislocations along and perpendicular to the boundaries. The latter contributes to a large-scale fluctuation of the orientation of the crystal but the former does not. The transition temperatures of these transitions are very different, with the latter occuring at a much higher temperature. Order-of-magnitude estimates of these temperatures are consistent with recent experimental results from elasticity and X-ray measurements in solid 4He.

67.80.-s - Quantum solids.

© EPLA 2009