Quantum dots desorption via high-power Nd:YAG laser pulses

Abstract

In the present work, we investigated the mechanism behind the desorption of quantum dots (QDs) CdSe/ZnS (core/shell) aggregates via Q-switched Nd:YAG pulsed laser. After desorption, we trapped the aggregates in a linear quadrupole Paul trap and analyzed their dynamics using machine vision methods. We found that the number of desorbed aggregates is proportional to the laser radiation energy. The injection efficiency was 13.6% for all values of the laser pulse energy greater than 200 mJ. However, even thoughthe desorption process was also observed at lower values (<200 mJ), we did not register particles trapping in this case. This effect might be caused by the different nature of desorption at low powers (LIAD) and at high powers (desorption as a result of substrate ablation).