Fatigue processes in triglycine sulfate and the effect of a magnetic field on them

For the first time, fatigue processes in triglycine sulfate crystals were studied using a combination of electrical and scanning probe microscopy methods. Long-term ($>$ 100 h) influence of a sinusoidal field with a frequency of 50 Hz and an amplitude of 1 kV/cm lead to a sharp decrease of the permittivity in the phase transition region and degradations of $P$–$E$ hysteresis loops (a decrease of spontaneous polarization, an increase of coercive and bias fields). Changes in dielectric properties were accompanied by an increase of the defect nanoclusters density and broadening their size distribution spectrum on the (010) cleavage surface. A subsequent exposure of “fatigued” crystals in the static magnetic field of 2 T for 20 min led to hysteresis loop symmetrization, which indicates a magnetoinduced transformation in the structure of defects responsible for fatigue effects.