Spectral and temporal optical signal generation using randomly distributed quantum dots

Quantum dots (QDs) have a great potential for realizing information processing because of their signal-modulation capability based on energy transfer. We present a method for generating diverse temporal and spectral signals based on the energy transfer between multiple QDs. The method uses randomly distributed QDs, so it is not necessary to precisely arrange a QD network. With multiple energy transfers between QDs, a variety of signals within the QD network can be generated by optical inputs. Experimental results revealed that fluorescence decays of dense QDs were faster when the density of QDs or the irradiation intensity decreased. Furthermore, depending on the positions, stacked QDs showed different spectral responses. The randomly distributed QDs can generate diverse signals, which is essential for signal processing to handle temporal information.