Metamaterials are the artificial components which have extraordinary optical properties. Extraordinal transmission, negative index, and super resolution can be realized by metamaterials. We aim to realize high performance electronic devices by utilizing specific optical properties acquired by metamaterials.
Metamaterial thermoelectric conversion
We propose a thermoelectric device that can produce a thermal gradient even in a uniform-temperature environment. We introduced a metamaterial absorber (MA), which comprised a transparent calcium fluoride layer sandwiched between a silver mirror layer and silver microdisk arrays, at one end of a thermoelectric device made of bismuth antimony telluride. The heating efficiencies of the MA and opposite electrodes of the device were unbalanced; consequently, the Seebeck effect was induced, resulting in electricity generation. We fabricated the MA on a copper electrode loaded on a thermoelectric device, and the device was placed in a uniform-temperature environment at 364 K. The thermal gradient across the device was experimentally measured and was found to be 0.14 K.
R. Nakyama, S. Sohei, T. Tanaka, and W. Kubo*, “Metasurface absorber enhanced thermoelectric conversion”, arXiv:2308.05956. [Link]
T. Asakura, T. Odaka, R. Nakayama, S. Saito, S. Katsumata, T. Tanaka, and W. Kubo* “Metamaterial Thermoelectric Conversion “, arXiv.[Link]
S. Katsumata, T. Tanaka, and W. Kubo* “Metamaterial perfect absorber for intensifying thermal gradient across thermoelectric device”, Optics Express, 29, 16396-16405, 2021. [Link]
Photodetector
Plasmonic photo-thermoelectric conversion is a completely novel optoelectronic conversion mechanism that converts optical energy into electricity through the localized heat of plasmons. Plasmonic photo-thermoelectric devices are composed of plasmonic structures for light detection and thermoelectric conversion materials for electricity generation. It is an optoelectronic converter that allows for the selection of the driving wavelength. In the future, we expect its application in low-temperature waste heat energy recovery devices and high-sensitivity light detectors.
M. Horikawa, X. Fang, and W. Kubo* “Metamaterial perfect absorber-enhanced plasmonic photo-thermoelectric conversion”, Applied Physics Express, 13, 082006, 2020.[Link]
K. Miwa, H. Ebihara, X. Fang, W. Kubo* “Photo-thermoelectric Conversion of Plasmonic Nanohole Array”, Applied Sciences, 8, 2681, 2020.[Link]
W. Kubo*, M. Kondo, and K. Miwa, “Quantitative Analysis of the Plasmonic Photo-thermoelectric Phenomenon”, J. Phys. Chem. C, 123, 21670-21675, 2019. [Link]