Superconducting infrared nanobolometers with on-chip photon-sorting metasurfaces

Superconducting bolometric detectors offer unrivaled sensitivity across a broad spectral range. However, their multispectral resolving capability is fundamentally constrained by a reliance on bulky external elements such as beam splitters, filters, or spectrometers. To overcome this limitation, we report an on-chip photon-sorting superconducting infrared nanobolometer based on a dual-band metal–insulator–metal metasurface. The device utilizes a nested two-channel Nb nanowire architecture to achieve simultaneous plasmonic infrared harvesting, spectral sorting, and photoelectric conversion within a single structure. At 5.7 K, the bolometer exhibits distinct responsivity peaks at ∼1025 cm−1 (9.7×106 V/W) and ∼1377 cm−1 (3.7×107 V/W), with a photon-sorting efficiency exceeding 70%. This integrated device provides a compact and highly sensitive platform for infrared photodetection, with direct applications in weak-light thermal imaging and precision temperature sensing.