Plasmonic-Layered InAs/InGaAs Quantum-Dots-in-a-Well Pixel Detector for Spectral-Shaping and Photocurrent Enhancement

• Main Authors: Jehwan Hwang, Zahyun Ku, Jiyeon Jeon, Yeongho Kim, Jun Oh Kim, Deok-Kee Kim, Augustine Urbas, Eun Kyu Kim, Sang Jun Lee
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Nanomaterials
• Subjects: spectral imaging; plasmonic resonance; metal hole array; quantum dots-in-a-well; electromagnetic simulation
• Online Access: https://www.mdpi.com/2079-4991/10/9/1827

The algorithmic spectrometry as an alternative to traditional approaches has the potential to become the next generation of infrared (IR) spectral sensing technology, which is free of physical optical filters, and only a very small number of data are required from the IR detector. A key requirement is that the detector spectral responses must be engineered to create an optimal basis that efficiently synthesizes spectral information. Light manipulation through metal perforated with a two-dimensional square array of subwavelength holes provides remarkable opportunities to harness the detector response in a way that is incorporated into the detector. Instead of previous experimental efforts mainly focusing on the change over the resonance wavelength by tuning the geometrical parameters of the plasmonic layer, we experimentally and numerically demonstrate the capability for the control over the shape of bias-tunable response spectra using a fixed plasmonic structure as well as the detector sensitivity improvement, which is enabled by the anisotropic dielectric constants of the quantum dots-in-a-well (DWELL) absorber and the presence of electric field along the growth direction. Our work will pave the way for the development of an intelligent IR detector, which is capable of direct viewing of spectral information without utilizing any intervening the spectral filters.