Voltage-controlled reversible modulation of colloidal quantum dot thin film photoluminescence

Active modulation of quantum dot thin film photoluminescence (PL) has been far-reaching potential applications in biomedical and optoelectronic systems, but challenges remain achieving large PL depth fast temporal response. Here, we report an efficient voltage-controlled optical down-converter by optically exciting a colloidal within light-emitting diode under reverse bias. Utilizing field-induced luminescence quenching, show that electric field can strongly modify carrier dynamics this nanostructured device, resulting stable reversible quenching. The device exhibits reduction up to 99.5%, corresponding contrast ratio 200:1 the applied 3 MV cm −1 with 300 ns response time. Using excitation wavelength dependent transient spectroscopy, further high degree quenching is achieved synergistic interplay quantum-confined Stark effect exciton dissociation.