Guided-Mode Resonator Coupled with Nanocrystal Intraband Absorption

• DOI: 10.1021/acsphotonics.1c01847
• Publication Date: 2022-02-10T14:22:52Z
• Authors: Adrien Khalili; Mateusz Weis; Simon Gwénaël Miz...; Audrey Chu; Tung Huu Dang; Claire Abadie; Charlie Gréboval; Corentin Dabard; Yoann Prado; Xiang Zhen Xu; Emmanuel Péronne; Clément Livache; Sandrine Ithurria; Gilles Patriarche; Julien Ramade; Grégory Vincent; Davide Boschetto; Emmanuel Lhuillier
• Keywords: intraband absorption; optical resonator; mid-infrared; mercury chalcogenides; [CHIM.MATE]Chemical Sciences/Material chemistry; 02 engineering and technology; [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]; 0210 nano-technology; 530; doped nanocrystals; 620

International audience<br/>Intraband absorption in doped nanocrystals offers an interesting alternative to narrow band gap materials to explore mid infrared optoelectronic device designs. However, the performance of such device clearly lags behind the ones relying on intrinsic materials. Livache et al. have proposed a dye sensitized approach to overcome the limitations observed from intraband materials (high dark current, slow response, low activation energy), where the intraband absorber is coupled to an undoped material which takes care of the charge conduction. Here, we unveil the coupling between both materials using mid-infrared transient reflectivity (TR) measurement. We show that hybrid material displays a unique feature in the TR signal that we attribute to a charge transfer and for which the dynamic matches the hopping time. We then developed a strategy to enhance the photodetection performances of the hybrid material by coupling for the first time intraband absorption to a light resonator. The latter is used to enhance the absorption by a factor 4 and enables an increase of the operating temperature by 80 K compared to the reference device. The obtained device matches the performance of best devices relying on intraband absorption.<br/>