A CdSe quantum dot based resonant cavity light-emitting diode showing single line emission up to 90 K

A II-VI wide-bandgap resonant cavity light-emitting diode is presented. The active region consists of CdSe quantum dots embedded in ZnSSe/MgS barriers, resulting in improved quantum efficiency at elevated temperatures. The resonant cavity is formed by a 14-period bottom distributed Bragg reflector and the semiconductor to air interface on top of the structure. Temperature dependent micro-electroluminescence measurements reveal emission of a single quantum dot up to 90 K. The turn-on voltages are 6 V at 4 K and 4 V at room temperature. These results are promising for the realization of green surface-emitting devices in general, and especially for an electrically driven prospective single photon source operating at room temperature.