Plasmon-Enhanced Light Absorption in Mid-Wavelength Infrared HgCdTe Detectors

• Published in: IEEE journal of selected topics in quantum electronics Vol. 28; no. 2: Optical Detectors; pp. 1 - 10
• Main Authors: Vallone, Marco, Tibaldi, Alberto, Hanna, Stefan, Wegmann, Anne, Eich, Detlef, Figgemeier, Heinrich, Bertazzi, Francesco, Ghione, Giovanni, Goano, Michele
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Absorbers; Absorption; Crosstalk; Detectors; Electromagnetic absorption; Electromagnetics; Faces; FDTD; focal plane arrays; Focal plane devices; Gold; HgCdTe; Infrared detectors; Mercury cadmium tellurides; Nanorods; Photovoltaic cells; Pixels; Plasmonics; Plasmons; Polaritons; Reduction; Shape
• ISSN: 1077-260X; 1558-4542
• DOI: 10.1109/JSTQE.2021.3111780

Multiphysics modeling of a planar HgCdTe-based mid-wavelength infrared (MWIR) focal plane array with <inline-formula><tex-math notation="LaTeX">3\,\mu</tex-math></inline-formula>m-wide pixels enlightens the role of surface plasmon-polaritons observed in gold nanorods arranged on its illuminated face. Simulations indicate that the proposed plasmonic detector, which employs a <inline-formula><tex-math notation="LaTeX">1\,\mu</tex-math></inline-formula>m-thick absorber layer, exhibits a reduction of diffusive inter-pixel crosstalk by more than one order of magnitude with respect to more conventional, non-plasmonic detectors with a <inline-formula><tex-math notation="LaTeX">5\,\mu</tex-math></inline-formula>m-thick absorber layer, without penalizing responsivity and achieving increased detectivity in the whole MWIR band by taking advantage of the absorber volume reduction.