All-epitaxial long-range surface plasmon polariton structures with integrated active materials

Abstract

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.

Plasmonics: Enabling functionalities with novel materials

“…11 Operating regimes of graphene plasmonic field-effect transistors (FETs) are proposed by Zhang and Shur. 12 The unidirectional propagation of SPP waves in a nanolaser based on a graphene-insulator-metal (GIM) platform paves the way for the future development of plasmonic circuitry using GIM platforms that can perform fast signal modulation and processing according to the recent results discussed by Li et al 13 All-epitaxial structures consisting of type-II superlattice materials quantum engineered by sandwiching a heavily doped semiconductor layer acting as plasmonic thin film are demonstrated by Nordin et al 14 to support short-and long-range surface plasmon polariton (SRSPP and LRSPP) modes in the long-wave infrared region of the electromagnetic spectrum.…”

High operating temperature plasmonic infrared detectors

“…See the supplementary material for x-ray diffraction measurements of as-grown device material. 33 The first three generations of plasmonic detectors (T max = 170, 185, 195K) used superlattice absorbers with decreasing period (40, 35, 30 ML) and superlattice (SL) barriers. Decreasing the absorber SL period blue-shifts the effective bandgap (as seen in the λ 1%EQE max column), with little to no effect on the position of the absorption peak, and subsequent position of λ 50% EQE max .…”

“…The demonstrated detectors highlight only one of a range of optical designs incorporating integrated plasmonic layers. There exists considerable potential for LWIR detector architectures with enhanced functionality, such as ultra-fast detection, or spectrally tunable/switchable detection which could be enabled by different plasmonic optoelectronic architectures 33 . The detectors demonstrated here are thus an important step towards room temperature devices, as well as device architectures with the potential to extend the limits of LWIR detection and detector functionality.…”

Simulational investigation of self-aligned bilayer linear grating enabling highly enhanced responsivity of MWIR InAs/GaSb type-II superlattice (T2SL) photodetector

“…InAs/GaSb Type II Superlattice (T2SL) on GaSb substrate has emerged as a potential photodetector material, offering high performance by exceptional quantum efficiency and low dark current levels, which enables state-of-art infrared detection by controlling the band gap of an InAs/GaSb T2SL 16 , 17 . Coupling a detector with resonant structures such as Fabry–Perot 18 , 19 and surface plasmon modes 20 offer both resonant and broadband enhancement, which enables the encoding of spectral and polarization information, significantly enhancing the detector's signal-to-noise characteristics 21 – 26 .…”