Diffusion by jumps of off-center impurities in a double-well potential is considered in metals. It is shown that successive jumps of the impurity atom caused by the long-range interactions constitute diffusive motion occurring in random manner as transfer of a "defect" resembling a domain wall in ferromagnetic or ferroelectric materials. We consider the conditions of the dominating contribution of the off-center mechanism in the impurity transfer. We show that the crossover from the thermal activated diffusion to Brownian motion may occur at high temperatures, when it is accompanied by the enhancement of the diffusion.
|Number of pages
|Physics Letters, Section A: General, Atomic and Solid State Physics
|Published - 2 Sep 2002
Bibliographical noteFunding Information:
We are grateful to the German–Israeli Research Foundation, GIF, No. G-703-41.10/2001 for support. One of us (A.G.) is indebted to P. Wyder for his cooperation in Ref.  leading to a part of the results presented here.
ASJC Scopus subject areas
- General Physics and Astronomy