Influence of absorbed dose and deep traps on thermoluminescence response: a numerical simulation

Numerical simulations based on standard rate equations are carried out to study the dependence of the thermoluminescence (TL) response on the absorbed dose. The model, which includes thermally stimulated exoelectronic emission (TSEE), uses three electron traps--two active and one thermally disconnected (TD)--and one deep hole trap acting as a recombination centre. After instantaneous creation of a given dose of electron-hole pairs, one first follows isothermal recombination and trap filling before simulating the TL readout. Influence of TD traps and specific effects due to trap saturation are illustrated. A systematic study of the TL response is performed in wide ranges of the determining parameters. The dose dependence is found to be quadratic, linear or intermediate according to their relative values. Results are explained in terms of recombination-trapping competition, trap occupancy and in relation with the presence of TSEE.