Enhanced Photocurrent and Electrically Pumped Quantum Dot Emission from Single Plasmonic Nanoantennas
In a realm where light and matter intertwine at the nanoscale, our research explores a cost-effective, self-assembly approach to craft quantum dot (QD) nanoantennas that can be activated electrically. QDs are tiny nanocrystals that act like miniature light bulbs. Our plasmonic nanoantennas can tightly trap light on the embedded QDs, enhancing their efficiency and speed interacting with photons. Our experiments over extensive optical and electrical measurements showcase robust photo-response behaviours. They showcase light emission powered by electricity with remarkable long-term stability, illustrating the potential for efficient and durable optoelectronic components. Our devices also reveal a giant voltage-dependent colour shift in emission. Our findings foster a new route to bright, high-speed, tunable, on-chip light sources under ambient conditions.
The figure shows electroluminescence of such a QD-nano-device. (a) Schematic of single junction electroluminescence (EL) experiment. (b) Top panel: bias voltage (grey) and current (blue) vs time during electrical pumping of a single QD nano-device; middle panel: time trace of total EL intensity and EL image (inset); bottom panel: time evolution of QD EL spectrum. (c) Experimental angular emission pattern using optical (blue) and electrical (red) excitation (0° is normal to the sample plane). (d) EL spectra of nanoantenna-dressed QD in weak (blue) and strong (red) coupling regimes.