Derivation of an activation energy spectrum for defect processes from isothermal measurements, using a minimization principle and Fourier analysis

The authors present a method to calculate the activation energy spectrum (AES) for defect processes from isothermal data, based on a minimization principle (smoothest possible spectrum compatible with the experimental data). This principle leads to a matrix relation, from which the AES can be calculated in a very simple way, if the relevant functions are Fourier transformed. A window function suited to AES calculations is derived. The method is tested for simulated and experimental data. It appears to be rapid and flexible. In principle the number of input data can be made very large, leading to a sharp energy resolution.