Incommensurate phases soliton structure

One can show that the Cl transition occurs at uc = n2n2a2/16y2. The incommensurate phase (for v < uc) consists of a periodic arrangement of regions where the phase is nearly constant, separated by walls where p(x) increases by 2njn (see fig. 24 for n = 1). One describes this structure as a domain wall lattice or soliton lattice , whose lattice constant ld... 

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