TY - JOUR
T1 - Selective absorption of a thermophotovoltaic cell using a thin semiconductor and a top fishnet-structured electrode
AU - Isobe, Kazuma
AU - Hanamura, Katsunori
N1 - Funding Information:
The authors would like to thank the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant in Aide (Number: 17H03184 ) for the financial support.
Publisher Copyright:
© 2019 Elsevier Ltd
PY - 2019/5
Y1 - 2019/5
N2 - The electromagnetic field around a thermophotovoltaic (TPV) cell made of a metal–semiconductor–metal (MSM) multilayer with a square-grid electrode layer, referred to as a fishnet layer, was numerically calculated using a three-dimensional finite difference time domain method to obtain the absorptance of the MSM multilayer. In this study, gold and gallium antimony assumed to be materials of the metal and semiconductor layer, respectively. Even if there was no top metal layer, several peaks of absorptance were observed because of the optical interference inside the gallium antimony thin film. Here, the peak wavelength shifted to a shorter wavelength region by placing a fishnet layer on the gallium antimony layer. Moreover, the wavelength of the first peak of the optical interference could be adjusted at the active range of wavelength from 0.8 um to 1.8 um for the TPV cell made of gallium antimony for a practical power generation system. As a result, even in a several hundred nanometers thickness of semiconductor, a 60% of radiant energy absorbed could be concentrated in the active range of wavelength that is defined as a spectral efficiency. From the simulation results with an equivalent waveguide model, the shift of the first peak using the fishnet layer could be described using a dispersion relation of the waveguide, which was fulfilled with gallium antimony. Moreover, the superposition of different resonant modes originated from the waveguide-like structure and strip-wired structure affected the spectral absorption of the MSM multilayer when the wall of the fishnet structure was expanded.
AB - The electromagnetic field around a thermophotovoltaic (TPV) cell made of a metal–semiconductor–metal (MSM) multilayer with a square-grid electrode layer, referred to as a fishnet layer, was numerically calculated using a three-dimensional finite difference time domain method to obtain the absorptance of the MSM multilayer. In this study, gold and gallium antimony assumed to be materials of the metal and semiconductor layer, respectively. Even if there was no top metal layer, several peaks of absorptance were observed because of the optical interference inside the gallium antimony thin film. Here, the peak wavelength shifted to a shorter wavelength region by placing a fishnet layer on the gallium antimony layer. Moreover, the wavelength of the first peak of the optical interference could be adjusted at the active range of wavelength from 0.8 um to 1.8 um for the TPV cell made of gallium antimony for a practical power generation system. As a result, even in a several hundred nanometers thickness of semiconductor, a 60% of radiant energy absorbed could be concentrated in the active range of wavelength that is defined as a spectral efficiency. From the simulation results with an equivalent waveguide model, the shift of the first peak using the fishnet layer could be described using a dispersion relation of the waveguide, which was fulfilled with gallium antimony. Moreover, the superposition of different resonant modes originated from the waveguide-like structure and strip-wired structure affected the spectral absorption of the MSM multilayer when the wall of the fishnet structure was expanded.
KW - Finite difference time domain method
KW - Fishnet-structured electrode
KW - Metal–semiconductor–metal multilayer
KW - Metamaterial
KW - Optical interference
KW - Thermophotovoltaic cell
KW - Waveguide theory
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U2 - 10.1016/j.ijheatmasstransfer.2019.01.087
DO - 10.1016/j.ijheatmasstransfer.2019.01.087
M3 - Article
AN - SCOPUS:85060515715
VL - 134
SP - 807
EP - 814
JO - International Journal of Heat and Mass Transfer
JF - International Journal of Heat and Mass Transfer
SN - 0017-9310
ER -