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We demonstrate a room-temperature all-epitaxial guided-mode resonance light-emitting diode operating in the mid-wave infrared. The device comprises a dielectric waveguide with an AlGaAsSb p−i−n diode core, below a layer of grating-patterned GaSb and above a highly doped, and thus, low index, InAsSb layer. Light emitted from the device active region into propagating modes in the waveguide scatters into free space via the GaSb grating, giving rise to spectrally narrow features that shift with emission angle across much of the mid-wave infrared. For collection angles approaching 0°, we are able to obtain linewidths of ∼2.4 meV across the spectral/angular emission of the LED, corresponding to λ/Δλ∼570. Fine control of emission wavelength can be achieved by tuning the applied current, which causes a redshift of approximately 20 nm due to the thermo-optic effect. The presented device has the potential for use in compact, high bandwidth, and low-cost mid-wave infrared sensing applications requiring spectral discrimination.

 

Plasmonic materials, and their ability to enable strong concentration of optical fields, have offered a tantalizing foundation for the demonstration of sub-diffraction-limit photonic devices. However, practical and scalable plasmonic optoelectronics for real world applications remain elusive. In this work, we present an infrared photodetector leveraging a device architecture consisting of a “designer” epitaxial plasmonic metal integrated with a quantum-engineered detector structure, all in a mature III-V semiconductor material system. Incident light is coupled into surface plasmon-polariton modes at the detector/designer metal interface, and the strong confinement of these modes allows for a sub-diffractive ($\sim <\#comment/>{\mathrm{\lambda <\#comment/>}}_0/33$) detector absorber layer thickness, effectively decoupling the detector’s absorption efficiency and dark current. We demonstrate high-performance detectors operating at non-cryogenic temperatures ($T=195\mathrm{K}$), without sacrificing external quantum efficiency, and superior to well-established and commercially available detectors. This work provides a practical and scalable plasmonic optoelectronic device architecture with real world mid-infrared applications.

 

Infrared detectors using monolithically integrated doped semiconductor “designer metals” are proposed and experimentally demonstrated. We leverage the “designer metal” groundplanes to form resonant cavities with enhanced absorption tuned across the long-wave infrared (LWIR). Detectors are designed with two target absorption enhancement wavelengths: 8 and 10 μm. The core of our detectors are quantum-engineered LWIR type-II superlattice p-i-n detectors with total thicknesses of only 1.42 and 1.80 μm for the 8 and 10 μm absorption enhancement devices, respectively. Our 8 and 10 μm structures show peak external quantum efficiencies of 45 and 27%, which are 4.5× and 2.7× enhanced, respectively, compared to control structures. We demonstrate the clear advantages of this detector architecture, both in terms of ease of growth/fabrication and enhanced device performance. The proposed architecture is absorber- and device-structure agnostic, much thinner than state-of-the-art LWIR T2SLs, and offers the opportunity for the integration of low dark current LWIR detector architectures for significant enhancement of IR detectivity.