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 ( ∼ λ 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 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.

Epitaxial heterostructures of narrow-gap IV-VI and III-V semiconductors offer a platform for new electronics and mid-infrared photonics. Stark dissimilarities in the bonding and the crystal structure between the rocksalt IV–VIs and the zincblende III–Vs, however, mandate the development of nucleation and growth protocols to reliably prepare high-quality heterostructures. In this work, we demonstrate a route to single crystal (111)-oriented PbSe epitaxial films on nearly lattice-matched InAs (111)A templates. Without this technique, the high-energy heterovalent interface readily produces two populations of PbSe grains that are rotated 180° in-plane with respect to each other, separated by rotational twin boundaries. We find that a high-temperature surface treatment with the PbSe flux extinguishes one of these interfacial stackings, resulting in single-crystalline films with interfaces that are mediated by a monolayer of distorted PbSe. While very thin PbSe-on-InAs films do not emit light, hinting toward a type-III band alignment, we see strong room temperature photoluminescence from a 1.5 μm thick film with a minority carrier lifetime of 20 ns at low-excitation conditions and bimolecular recombination at high excitation conditions, respectively, even with threading dislocation densities exceeding 108 cm−2. We also note near-complete strain relaxation in these films despite large thermal expansion mismatch to the substrate, with dislocations gliding to relieve strain even at cryogenic temperatures. These results bring to light the exceptional properties of IV-VI semiconductors and the new IV-VI/III-V interfaces for a range of applications in optoelectronics.

Cascaded superlattice LEDs were designed, grown, fabricated, and tested with an n-type anode structure consisting of a variably doped n-GaSb buffer layer and a variable tunnel junction of n-GaxIn1−xAsySb1−y/p-GaSb in place of a conventional p-doped anode contact layer. The elimination of p-doped contact layers from the structure was found to reduce parasitic optical absorption and ohmic loss. After selecting the ideal design from the 4 stage test structures, a nominally identical 16 stage n-type anode structure was grown, yielding an MWIR radiance of 6.7 W/cm2/sr.

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Monolithically combining silicon nitride ( S i N x ) photonics technology with III-V active devices could open a broad range of on-chip applications spanning a wide wavelength range of ∼ 400 − 4000 n m . With the development of nitride, arsenide, and antimonide lasers based on quantum well (QW) and quantum dot (QD) active regions, the wavelength palette of integrated III-V lasers on Si currently spans 400 nm to 11 µm, with a crucial gap in the red-wavelength regime of 630–750 nm. Here, we demonstrate red I n 0.6 G a 0.4 P QW and far-red InP QD lasers monolithically grown on CMOS-compatible Si (001) substrates with continuous-wave operation at room temperature. A low-threshold current density of 550 A / c m 2 and 690 A / c m 2 with emission at 680–730 nm was achieved for QW and QD lasers on Si, respectively. This work represents a step toward the integration of visible red lasers on Si, allowing the utilization of integrated photonics for applications including biophotonic sensing, quantum computing, and near-eye displays.

Two new superlattices with high internal quantum efficiency at high injection, InAs/AlGaInSb and InAs/GaInSb/InAs/AlAsSb, are presented and compared with state-of-the-art InAs/GaSb and InAs/InAsSb superlattices. The internal quantum efficiency peaks at 44% and 77% for the InAs/AlGaInSb and InAs/GaInSb/InAs/AlAsSb samples, respectively, which suggests that they are excellent candidates for high-efficiency mid-wave infrared LEDs. These values have been measured without invoking the ABC model to eliminate the assumption of Boltzmann statistics. The calculated superlattice band structures are used qualitatively to explain the internal quantum efficiency results.

We demonstrate all-epitaxial structures capable of supporting short- and long-range surface plasmon polariton (SRSPP and LRSPP) modes in the long-wave infrared region of the electromagnetic spectrum. The SRSPP and LRSPP modes are bound to the interfaces of a buried heavily doped (n++) semiconductor layer and surrounding quantum-engineered type-II superlattice (T2SL) materials. The surrounding T2SLs are designed to allow optical transitions across the frequency dispersion of the SPP modes. We map the SPP dispersion in our structure using grating-coupled angle- and polarization-dependent reflection and photoluminescence spectroscopy. The epitaxial structures are analytically described using a simplified three-layer system (T2SL/n++/T2SL) and modeled using rigorous coupled wave analysis with excellent agreement to our experimental results. The presented structures offer the potential to serve as long-range interconnects or waveguides in all-epitaxial plasmonic/optoelectronic systems operating in the long-wave infrared.

Remarkable systems have been reported recently using the polylithic integration of semiconductor optoelectronic devices and plasmonic materials exhibiting epsilon-near-zero (ENZ) and negative permittivity. In traditional noble metals, the ENZ and plasmonic response is achieved near the metal plasma frequency, limiting plasmonic optoelectronic device design flexibility. Here, we leverage an all-epitaxial approach to monolithically and seamlessly integrate designer plasmonic materials into a quantum dot light emitting diode, leading to a 5.6 × enhancement over an otherwise identical non-plasmonic control sample. The device presented exhibits optical powers comparable, and temperature performance far superior, to commercially available devices.