Comment on “The defect density waves in Zn _0.98 Sn _0.02 TiO ₄ single crystal with incommensurately modulated structures: Neutron diffraction study” by Y. Park

Abstract

In a recent letter (Europhys. Lett., 52 (2000) 557), Park discusses the formation of defect density waves (DDW) in a modulated system and a multiwave state explained in terms of a superposition of several modulations along a single crystallographic direction. We show that the structural evidence of DDW and of memory effects has been known for some time. Moreover, the figures on which Park bases his discussion contain apparent inconsistencies.