Epitaxial mid-IR nanophotonic optoelectronics

• Published in: Applied physics letters 2022-05, Vol.120 (22)
• Main Authors: Nordin, L., Wasserman, D.
• Format: Article
• Language: English
• Subjects: Applied physics; Computer architecture; Devices; Dielectric waveguides; Diffraction; Optoelectronic devices; Optoelectronics; Plasmonics; Wavelengths
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/5.0086774

There are a range of fundamental challenges associated with scaling optoelectronic devices down to the nano-scale, and the past decades have seen significant research dedicated to the development of sub-diffraction-limit optical devices, often relying on the plasmonic response of metal structures. At the longer wavelengths associated with the mid-infrared, dramatic changes in the optical response of traditional nanophotonic materials, reduced efficiency optoelectronic active regions, and a host of deleterious and/or parasitic effects makes nano-scale optoelectronics at micro-scale wavelengths particularly challenging. In this Perspective, we describe recent work leveraging a class of infrared plasmonic materials, highly doped semiconductors, which not only support sub-diffraction-limit plasmonic modes at long wavelengths, but which can also be integrated into a range of optoelectronic device architectures. We discuss how the wavelength-dependent optical response of these materials can serve a number of different photonic device designs, including dielectric waveguides, epsilon-near-zero dynamic optical devices, cavity-based optoelectronics, and plasmonic device architectures. We present recent results demonstrating that the highly doped semiconductor class of materials offers the opportunity for monolithic, all-epitaxial, device architectures out-performing current state of the art commercial devices, and discuss the perspectives and promise of these materials for infrared nanophotonic optoelectronics.