skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Design of Selective Metasurface Filter for Thermophotovoltaic Energy Conversion
Optical filters with narrow transmission band above the bandgap of thermophotovoltaic (TPV) cells are not restrained by the rigorous thermal reliability as needed for the emitters. In this work, a novel metasurface filter made of an aluminum nanopillar (AlNP) array on a quartz substrate is proposed to achieve spectrally selective transmission above the bandgap of the TPV cell. Optical simulations using Finite-difference time-domain were carefully performed to determine the appropriate AlNP period, diameter, and height such that the resulting nanopillar array will show narrowband transmission at a wavelength of 1.9 μm, which is close to the bandgap of a commercial gallium antimonide (GaSb) TPV cell. The narrow-band transmission enhancement can be attributed to the magnetic polariton (MP) resonance between neighboring Al nanopillars. The MP mechanism is further confirmed by an inductor-capacitor circuit model and the effects of the nanopillars period, diameter, height, as well as incidence angles were discussed. Moreover, open-circuit voltage, short-circuit current density, output electric power, and conversion efficiency were evaluated for the GaSb TPV cell coupled with the AlNP metasurface filter structure with enhanced TPV performance.  more » « less
Award ID(s):
1944750
PAR ID:
10547419
Author(s) / Creator(s):
; ; ; ;
Corporate Creator(s):
; ; ;
Publisher / Repository:
Engineered Science
Date Published:
Journal Name:
ES Energy & Environment
ISSN:
2578-0646
Subject(s) / Keyword(s):
selective metasurface
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract— A promising technology for waste-heat recovery applications is thermophotovoltaics (TPVs), which use photovoltaic diodes to convert thermal energy into electricity. The most commonly used TPV diode material is gallium antimonide (GaSb). Recently, GaSb TPV diodes were fabricated with front-surface metallic photonic crystal (MPhC) filters to more optimally convert the incident spectrum. This method showed promising initial results, in part due to a shifting of the photogenerated carriers away from the front-surface and into the device. In this paper, we use the Atlas-Silvaco software package to optimize the TPV diode structure for MPhCs. We investigate the addition of an intrinsic region in the device to take advantage of the shifted photogeneration profile from the MPhCs. This design allows for a 10% improvement in internal quantum at the peak MPhC transmission wavelength. https://doi.org/10.1109/MWSCAS.2017.8053055 
    more » « less
  2. null (Ed.)
    This paper presents a circuit for simultaneous reception of optical power and data using a solar cell. The circuit employs a switched-inductor boost DC-DC converter for energy harvesting and a low-power thresholding receiver for data reception. The thresholding data receiver comprises a current-sense resistor that monitors the current output of the solar cell, an instrumentation amplifier, a band-pass filter and a comparator. A system-level analysis of an optical communication system employing the proposed circuit is presented along with a circuit-level analysis and implementation. As a proof-of-concept, the proposed circuit for simultaneous power and data reception is implemented using off-the-shelf components and tested using a custom-built test setup. Measurement results, including harvested power, electronic noise and bit error rate (BER), are reported for a GaAs solar cell and a red LED light source. Results show that 223 μW of power are harvested by the DC-DC converter at a distance of 32.5 cm and a radiated power of 9.3 mW. At a modulation depth of 50% and a transmission speed of 2.5 kbps, a BER of 1.008×10^-3 is achieved. Measurement results reveal that the proposed solution exhibits a trade-off between harvested power, transmission speed and BER. 
    more » « less
  3. Abstract The inherently weak chiroptical responses of natural materials limit their usage for controlling and enhancing chiral light-matter interactions. Recently, several nanostructures with subwavelength scale dimensions were demonstrated, mainly due to the advent of nanofabrication technologies, as a potential alternative to efficiently enhance chirality. However, the intrinsic lossy nature of metals and the inherent narrowband response of dielectric planar thin films or metasurface structures pose severe limitations toward the practical realization of broadband and tailorable chiral systems. Here, we tackle these problems by designing all-dielectric silicon-based L-shaped optical metamaterials based on tilted nanopillars that exhibit broadband and enhanced chiroptical response in transmission operation. We use an emerging bottom-up fabrication approach, named glancing angle deposition, to assemble these dielectric metamaterials on a wafer scale. The reported strong chirality and optical anisotropic properties are controllable in terms of both amplitude and operating frequency by simply varying the shape and dimensions of the nanopillars. The presented nanostructures can be used in a plethora of emerging nanophotonic applications, such as chiral sensors, polarization filters, and spin-locked nanowaveguides. 
    more » « less
  4. Properties of a double-period InAs/GaSb superlattice grown by solid-source molecular beam epitaxy are presented. Precise growth conditions at the InAs/GaSb heterojunction yielded abrupt heterointerfaces and superior material quality as verified by X-ray diffraction and transmission electron microscopy (TEM) analysis. Moreover, high-resolution TEM imaging and elemental composition profiling of the InAs/GaSb heterostructure demonstrated abrupt atomic transitions between each Sb- or As-containing epilayer. An 8 × 8 k · p model is used to compute the electronic band structure of the constituent long- and short-period superlattices, taking into account the effects of conduction and valence band mixing, quantum confinement, pseudomorphic strain, and magnetic field on the calculated dispersions. Magnetotransport measurements over a variable temperature range (390 mK to 294 K) show anisotropic transport exhibiting a striking magnetoresistance and show Shubnikov-de Haas oscillations, the latter being indicative of high quality material synthesis. The measurements also reveal the existence of at least two carrier populations contributing to in-plane conductance in the structure. 
    more » « less
  5. Thermophotovoltaics (TPVs) are a potential technology for waste-heat recovery applications and utilize IR sensitive photovoltaic diodes to convert long wavelength photons (>800nm) into electrical energy. The most common conversion regions utilize Gallium Antimonide (GaSb) as the standard semiconductor system for TPV diodes due to its high internal quantum efficiencies (close to 90%) for infrared radiation (~1700nm). However, parasitic losses prevent high conversion efficiencies from being achieved in the final device. One possible avenue to improve the conversion efficiency of these devices is to incorporate metallic photonic crystals (MPhCs) onto the front surface of the diode. In this work, we study the effect of MPhCs on GaSb TPV diodes. Simulations are presented which characterize a specific MPhC design for use with GaSb. E-field intensity vs. wavelength and depth are investigated as well as the effect of the thickness of the PhC on the interaction time between the e-field and semiconductor. It is shown that the thickness of MPhC has little effect on width of the enhancement band, and the depth the ideal p-i-n junction is between 0.6􀈝m and 2.1um. Additionally, simulated results demonstrate an increase of E-field/semiconductor interaction time of approximately 40% and 46% for a MPhC thickness of 350nm and 450nm respectively. 
    more » « less