Avalanches during recrystallization in radiation-damaged pyrochlore and allanite: Statistical similarity to phase transitions in functional materials

Differential scanning calorimetry has been employed to analyze the jerky behavior of exothermic, structural reorganization processes of the highly disordered radiation-damaged uranium or thorium containing minerals pyrochlore and allanite. The thermal signals occur as thermal spikes forming crackling noise spectra. The energy of the thermal spikes follows power-law behavior with an exponent ϵ ∼1.61-1.65, which is in good agreement with force integrated energy distributions predicted by mean field theory. The recrystallization is hence statistically identical to the collapse of martensites under external pressure and the switching of ferroelectric materials.