Polariton-enhanced multi-dimensional mid-infrared response devices

The mid-infrared (MIR, 2–25 μm) spectral range covers the molecular vibrational fingerprint region, two atmospheric windows (3–5 and 8–14 μm), and overlaps significantly with room-temperature blackbody radiation, making it invaluable for chemical and biomedical sensing, free-space communication, remote sensing, and thermal imaging. MIR response devices convert target characteristic information into detectable electrical, thermal, or optical signals, expanding the detection boundaries in critical application domains. However, conventional MIR response devices commonly face challenges such as cryogenic cooling dependence, large system volume, high cost, and reliance primarily on intensity response, making it difficult to identify complex backgrounds or camouflaged targets. MIR response devices designed based on polariton theory achieve on-chip acquisition of multi-dimensional optical field information including wavelength, intensity, and polarization through subwavelength-scale light field localization and mode control, promoting the evolution of MIR response devices from single intensity response to multi-dimensional information perception. This review discusses recent progress in polariton-enhanced multi-dimensional MIR response devices, detailing the working mechanisms of plasmon- and phonon-polaritons, and reviewing plasmon-enhanced devices based on metals, graphene, and black phosphorus, phonon-polariton-enhanced devices based on hexagonal boron nitride (hBN), α-MoO3, and silicon carbide (SiC), as well as the application status and inherent advantages of hybrid polaritons (graphene–metal, metal–SiO2, graphene–hBN/SiO2). This highlights that polariton enhancement plays a pivotal role in improving the sensitivity, integration, and information dimension acquisition of MIR response devices, and is expected to promote MIR response devices from single signal response toward a new stage of high sensitivity, on-chip, and multi-dimensional synergetic perception.