Defect induced lattice instabilities and competing interactions in niobium doped lead zirconate single crystals

Highlights: • Influence of intrinsic and created by doping crystal lattice defects at the example of Nb doped PbZrO₃ on phase transitions. • Existence of post- and pretransitional effects has been investigated for defects impact. • New phase transition has been investigated, not observed before in ceramics with the same nominal concentration of dopant. Influence of heterovalent Nb⁵⁺ doping of antiferroelectric PbZrO₃ single crystal has been investigated. This kind of doping, producing defects in the perovskite matrix, influences the lattice instabilities responsible for phase transition at T_C, and for inducing pre- and post-transitional effects. The dielectric, electromechanical, and optical properties were investigated. Opposite to their ceramic analogues, the investigated single crystals show a new phase transition and enlarged temperature ranges of lattice instabilities.