Animations
The films below show some exciting science we are doing.
Film 1: Demonstration of the smart materials functionality,
mediated by a domain-wall motion. This film shows the
artificially designed poly-domain structure, assembled from two
sets of tetragonal domains, marked by different colours (red or
blue). Here, external electric field controls the volume ratios
between these two domains and cumulative shape of the material.
Such domain-wall motion mediated deformation stands behind e.g.
super-elasticity and shape-memory effects in martensitic
alloys.
Film 2. Stroboscopically measured time-resolved powder diffraction profile. This animation demonstrates the time-dependence of {111} Bragg reflection from functional perovskite-based ferroelectric ceramics (0.94 BaTiO3 – 0.06 BiZn0.5Ti0.5O3) under cyclically applied 50 Hz external high-voltage. The yellow line shows time-dependence of the voltage. Further details are available in this paper. While watching this animation you should pay attention at the following.
Film 3. Determination of atomic displacements during polarization reversal in ferroelectric. This animation demonstrates how time-dependent change of Bragg intensity can be connected to the displacements of atoms in a unit cell. The red curve on the left panel the integrated intensity of {111} powder Bragg profile (as demonstrated in the previous film). The right panel shows a perovskite unit cell, in which A- and B- cations are displaced relative to the fixed oxygen octahedral cages. The blue curve on the left shows the structure factor-based simulation of {111} intensity variations. Further details are available here.
Film 4. Time-resolved X-ray diffraction study of Sr0.5Ba0.5Nb2O6 ferroelectric single crystal under cyclic electric field. This film demonstrates another output of stroboscopic X-ray diffraction experiment. Here the right panel shows the macroscopically measured polarization-electric field hysteresis loop. It is the type of hysteresis loop which you would find in classical physics textbooks. Such curve represents the change of macroscopic polarization to an applied electric field. The left panel shows X-ray diffraction rocking curve, measured with an open point detector. Each curve corresponds to a certain time, polarization and electric field, which is pinpointed in the hysteresis loop on the right. More details are available in this paper.