掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

DOI： 10.1021/acsphotonics.5c00124

PubMed

担当区分：責任著者   掲載種別：研究論文（学術雑誌）  

<jats:title>Abstract</jats:title>
<jats:p>Metasurface stickers, where the periodic array of nanoparticles is embedded in an elastomer film, can be attached to and detached from the surface of target materials and work as metasurface to control light. The stickers can be fabricated by lithographic and etching/lift-off processes, followed by a transfer process. To transfer, a sacrifice layer, typically water-soluble and oil-insoluble organic polymers, is required to separate the substrate from the metasurface. Although they fulfill the prerequisite as a sacrifice layer, organic polymers cannot be heated above 300 °C, and are often damaged during exposure to reactive gases in the dry etching processes. In this study, we introduced an alternative amorphous germanium dioxide (GeO<jats:sub>2</jats:sub>), an inorganic material with high water solubility, as the transfer sacrificial layer. The amorphous GeO<jats:sub>2</jats:sub>, made by mist chemical vapor deposition in this study, is stable and maintains the amorphous state under heat treatment up to 750 °C. Upon exposure to water, amorphous GeO<jats:sub>2</jats:sub> is readily nano-crystallized and dissolved while it is unsolved in organic solvents used in the nanofabrication processes. Using this sacrificial layer, we fabricated a TiO<jats:sub>2</jats:sub> metasurface sticker via nanoimprinting of a Ti film followed by thermal oxidation. We demonstrate a photoluminescence outcoupling by placing a sticker on the phosphor plate: the emission pattern is modulated both spatially and spectrally in a way defined by the structure of the metasurface sticker.</jats:p>

DOI： 10.35848/1347-4065/adb164

CiNii Research

その他URL： https://iopscience.iop.org/article/10.35848/1347-4065/adb164/pdf

担当区分：責任著者   掲載種別：研究論文（学術雑誌）  

DOI： 10.35848/1347-4065/adaecc

その他URL： https://iopscience.iop.org/article/10.35848/1347-4065/adaecc/pdf

担当区分：筆頭著者,　最終著者,　責任著者  

DOI： 10.1103/physreva.111.013511

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者  

DOI： 10.1117/12.3055231

担当区分：筆頭著者,　最終著者,　責任著者  

担当区分：筆頭著者,　最終著者,　責任著者  

掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

DOI： 10.1021/acsnano.4c09970

PubMed

CiNii Research

担当区分：筆頭著者,　最終著者,　責任著者  

<jats:p>We investigate the chiral emission from non-chiral molecules coupled to metasurfaces with a unit cell formed by dimers of detuned and displaced Si nanodisks. The detuning and displacement lead to the formation of narrow modes, known as quasi-bound states in the continuum (Q-BICs), with different electric and magnetic characteristics. The dispersion and character of the modes are explained by using the guided-mode expansion method and finite-element simulations. The coupling between these modes leads to an extrinsic chiral response with large circular dichroism for defined energies and wavevectors. When the lattice constant of the metasurface is changed, the dispersion of the extrinsic chiral Q-BICs can be tuned and the emission properties of a thin film of dye molecules on top of the metasurface are modified. In particular, we observe strongly directional and circularly polarized emission from the achiral dye molecules with a degree of circular polarization reaching 0.8 at the wavelengths defined by the dispersion of the Q-BICs. These results could enable the realization of compact light sources with a large degree of circular polarization for applications in displays, optical recording, or optical communication.</jats:p>

DOI： 10.1364/prj.528976

CiNii Research

掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

Fluorescent dye films on transparent substrates are essential for OLEDs, flexible displays, X-ray detection, and wireless optical communications. However, their efficiency is often hampered by fluorescence trapping due to total internal reflection (TIR) and waveguiding. This study tackles this longstanding challenge by reconceptualizing the integration of dye films with nanoantenna metasurfaces. Traditional methods involve directly spin-coating films onto c-Si metasurfaces on quartz substrates, resulting in edge luminescence and weak inner signals. We present a straightforward, adjustable approach by integrating dye films on the opposite side of quartz substrates, reaching a 2.5-fold photoluminescence enhancement and improving the uniformity of the emission compared to the conventional methods. These gains stem from redirecting a significant portion of leaked fluorescence light trapped inside the substrate into free space, surpassing TIR conditions through in-plane diffraction orders of the metasurfaces across the full RGB spectrum. Our findings facilitate the design of more efficient luminescent devices.

DOI： 10.1021/acs.nanolett.4c03294

PubMed

掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/adpr.202400050

担当区分：筆頭著者,　最終著者,　責任著者  

DOI： 10.2497/jjspm.23-00054

CiNii Research

掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

This work presents a bulk refractive index sensor based on quasi-bound states in the continuum (BICs) induced by broken symmetries in metasurfaces. The symmetry is broken by detuning the size and position of silicon particles periodically arranged in an array, resulting in multiple quasi-BIC resonances. We investigate the sensing characteristics of each of the resonances by measuring the spectral shift in response to changes in the refractive index of the surrounding medium. In addition, we reveal the sensing range of the different resonances through simulations involving a layer of deviating refractive index of increasing thickness. Interestingly, the resonances show very different responses, which we describe via the analysis of the near-field. This work contributes to the development of highly sensitive and selective BIC-based sensors that can be used for a wide range of applications.

DOI： 10.1364/OE.514787

PubMed

掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

H-type supramolecular polymers with preferred helicity and highly efficient emission have been prepared from the self-assembly of chiral tetraphenylene-based monomers. Implementation of the one-dimensional fibers into dielectric nanoparticle arrays allows for a significant reshaping of fluorescence due to weak light-matter coupling.

DOI： 10.1039/d3cc05877h

PubMed

担当区分：筆頭著者,　最終著者,　責任著者  

担当区分：筆頭著者,　最終著者,　責任著者  

担当区分：筆頭著者,　最終著者,　責任著者  

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