@article{jackson_kim_kim_canedy_juarez_ellis_nolde_aifer_iversen_burgner_et al._2024, title={Midwave infrared resonant cavity detectors with >70% quantum efficiency}, volume={125}, ISSN={["1077-3118"]}, DOI={10.1063/5.0243497}, abstractNote={We report resonant cavity infrared detectors with a peak wavelength of 4.54–4.58 μm that combine external quantum efficiency (EQE) exceeding 70% with spectral bandwidth 20–40 nm and ≤2% EQE at all non-resonance wavelengths between 4 and 5 μm. A 300-nm-thick absorber assures that most of the radiation propagating in the cavity produces photocurrent rather than parasitic loss. The cavity is formed by heterogeneously bonding a midwave infrared (MWIR) nBn detector chip to a GaAs/AlGaAs distributed Bragg reflector, etching away the GaSb substrate, forming mesas with diameter ≈100 μm, depositing a Ge spacer, and then depositing a single-period Ge-SiO2 top mirror. At all temperatures between 125 and 300 K, the responsivity at 150 mV bias exceeds 2.2 A/W and the EQE exceeds 61%. When the thermal background current for a realistic system scenario with f/4 optic that views a 300 K scene is derived from the observed EQE spectra, the resulting specific detectivity D* of 7.5 × 1012 cmHz½/W at 125 K operating temperature is 4.5 times higher than for a state-of-the-art broadband MWIR HgCdTe device. Simulations of the cavity performance indicate that EQE > 90% may be feasible following minimization of parasitic optical loss and maximization of the photocarrier collection efficiency. Potential applications include free space optical communication, chemical sensing, on-chip spectroscopy, and hyperspectral imaging.}, number={25}, journal={APPLIED PHYSICS LETTERS}, author={Jackson, E. M. and Kim, C. S. and Kim, M. and Canedy, C. L. and Juarez, X. G. and Ellis, C. T. and Nolde, J. A. and Aifer, E. H. and Iversen, C. and Burgner, C. and et al.}, year={2024}, month={Dec} }