Study of incommensurate modulation in V-doped La₂Cu_1-x(VO)_xO_{4 + δ}by transmission electron microscopy

Structural variations in a hole-rich grain of V-doped La2Cu1− x (VO) x O4+ δ (x = 0.045, δ = 0.011) superconducting compound have been studied by electron diffraction and high-resolution transmission electron microscopy. Two types of one-dimensional (1-D) incommensurate modulation were observed one after the other when the specimen was exposed to electron beam irradiation. The features of these two modulated structures have been studied and are discussed.