Toward nanocrystal-based active nanophotonic devices
Résumé
Optical properties tunability is one of the essential characteristics of nanocrystals (NCs). Nonetheless, obtaining reconfigurable spectral response in NC-based optoelectronic devices remains a hardly explored domain. This is because the conventional strategies, such as exploiting Stark effect or integrating NCs into MEMS structures, are not straightforward to apply for NC-based devices due to high electrostatic field requirement and fabrication incompatibility. Here, we demonstrate optical tunability with bias in a device coupling HgTe1 NCs with a plasmonic structure. Bias tunability can be obtained thanks to the interplay between absorption inhomogeneity due to the plasmonic cavity2 and the NC hopping transport. As a result, 15 meV blueshift can be observed under the application of 3 V bias voltage for a device working in the extended short-wave infrared3. We show that hopping transport, which is usually seen as a limitation of NCs, can be combined with inhomogeneous absorption to obtain an active photonic NC-based device.