Broadband perfect infrared absorbers using three-dimensional metamaterials

2022 Fiscal Year Final Research Report

• Project/Area Number: 18H03889
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 30:Applied physics and engineering and related fields
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Tanaka Takuo 国立研究開発法人理化学研究所, 開拓研究本部, 主任研究員 (40283733)
• Co-Investigator(Kenkyū-buntansha): 久保 若奈 東京農工大学, 工学(系)研究科(研究院), 准教授 (10455339)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: メタマテリアル / 光吸収体 / 赤外光 / 赤外分光 / 円錐螺旋構造 / 機械学習 / 光熱電変換デバイス

Outline of Final Research Achievements

We developed fabrication technique for three-dimensional vertical-Metal-Insulator-Metal (MIM) structure, in which MIM structure is orientated vertically on the substrate surface. Using this developed technique, we successfully fabricated the v-MIM structure and evaluated its optical properties using a Fourier-transform infrared spectrometer. The results showed that the developed v-MIM structure exhibits a resonant absorption band in the mid-infrared region, particularly demonstrating nearly complete light absorption of 99.5% at a wavelength of 5 μm. Furthermore, we demonstrated the expansion of the absorption wavelength range by integrating structures that has absorption bands at different wavelength regions. Broadband metamaterial absorber using hyperbolic metamaterial is also studied.

Free Research Field

メタマテリアル，ナノフォトニクス

Academic Significance and Societal Importance of the Research Achievements

本研究で開発したv-MIMメタマテリアルの加工技術は，極めて高いアスペクト比を持つ金属ナノ構造の加工技術として，高効率光吸収構造の加工に限らず幅広い分野に応用できる．例えば，現在半導体素子で主流となっているFin-FET素子や次世代のGAA素子では高いアスペクト比を持つナノ構造を高効率かつ大量に加工できる技術が求められている．本研究で開発した加工技術はこのような応用にも適用できる．また，v-MIM構造が赤外領域で高い光吸収特性を持つことを実証できた事に加え，複数の構造の集積化によって吸収帯域を広げる事にも成功した．試作した高効率赤外吸収体は赤外分光技術の高効率化にも貢献できると考えている．