Dynamics of twin boundaries in martensites

Abstract
The theory of forming a coherent twinning array in a parent phase is studied for a tetragonal to orthorhombic displacive transition. We find that this structure can be stabilized without the use of dislocations by a long-range interaction between the twin boundaries which is mediated via the parent phase. The dynamics of the twin boundary lattice consists of elementary excitations with surprisingly low frequency and a limiting (wave vector)1/2 dispersion.