Effect of thermal treatment on ZnSe quantum dots and energy transfer in borosilicate glasses doped with ZnSe and Er3+/ZnSe

This study assessed the effect of heat treatment on the spectroscopic properties of borosilicate glasses doped with ZnSe quantum dots (QDs) and co-doped with Er3+/ZnSe. The gradual growth of ZnSe QDs upon heat treatment was probed by TEM. The emission intensity of ZnSe-doped glasses rapidly increased up to 20 h of heat treatment because of the formation and development of ZnSe QDs, then gradually decreased due to the rise in non-radiative loss between the enlarged particles. With increasing number of ZnSe QDs, the energy transfer from QDs to Er3+ ions became prominent in Er3+/ZnSe-co-doped glasses, showing enhanced emission up to 20 h of heat treatment. The excited state 4S3/2 lifetime values, increased with heat treatment, whereas an opposite trend was observed for the lifetime values of state 4I13/2, indicating a possible participation of the ZnSe QDs in facilitating the energy migration mechanism through the 4I13/2 level, followed by non-radiative decay.

Automated summary

This study investigated the effect of heat treatment on the spectroscopic properties of borosilicate glasses doped with ZnSe quantum dots (QDs) and co-doped with Er3+/ZnSe. TEM analysis revealed the gradual growth of ZnSe QDs during heat treatment. The emission intensity of ZnSe-doped glasses initially increased due to the formation and development of ZnSe QDs, but gradually decreased as non-radiative loss between enlarged particles became dominant. The co-doped glasses showed enhanced emission up to 20 hours of heat treatment, indicating energy transfer from QDs to Er3+ ions.