Professor Si-Chen Lee

Graduate Institute of Photonics and Optoelectronics, National Taiwan University

臺灣大學光電所 李嗣涔教授

• “Localized shape resonance on silver film perforated by H-shaped and more complex shaped hole arrays”, Hao-Fu Huang, Yu-Wei Jiang, Hung-hsin Chen, Yi-Ting Wu, Yi-Tsung Chang, Fang-Tzu Chuang, and Si-Chen Lee, Optics express, Vol. 19, Iss. 6, pp. 5225–5231 (2011).

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  Fig. 1 (a) Top view and structure parameter of samples 1 to 3. (b) Zero-order transmission spectra at normal incidence of samples 1, 2, 3. The vertical red dash line represents the theoretical position of degenerated (1, 0) Ag/Si mode.

   

• “Wavelength Selective Plasmonic Thermal Emitter by Polarization Utilizing Fabry-Pèrot Type Resonances”, Pei-En Chang, Yu-Wei Jiang, Hung-Hsin Chen, Yi-Tsung Chang, Yi-Ting Wu, Lawrence Tzuang, Yi-Han Ye and Si-Chen Lee, Appl. Phys. Lett., 98, 073111 (2011).

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  Fig. 2 The schematic view of (a) a MIM PTE with rectangular metallic patch arrays as top layer. (b) Emittance spectra of three samples with all dx equal to 2 mm and dy = 3, 4 and 5 mm, respectively. The LSP (1, 0) and (0, 1) modes are at wavelength of about 6 mm and 8 mm, respectively. The green dotted curve is a fit of LSP (0, 1) to a Sin2θ dependence, while the blue fit curve of LSP (1, 0) to a Cos2θ dependence.

   

• “Hydrogenated Amorphous Silicon Solar Cell on Glass Substrate pattered by Hexagonal Nano-Cylinder Array”, Wei-Chen Tu, Yi-Tsung Chang, Chieh-Hung Yang, Dan-Ju Yeh, Chung-I Ho and Si-Chen Lee, Appl. Phys. Lett., 97, 193109 (2010).

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  Fig. 3 The SEM pictures of (a) the side view of the patterned solar cell on nano-cylinder array glass substrate. (b) The top view of the patterned solar cell after completion. (c) Measured EQE of flat and patterned solar cells.

Modal Characteristics of Antiresonant Reflecting Pipe Waveguides for Terahertz Waveguiding

Professor Hung-chun Chang

Graduate Institute of Photonics and Optoelectronics, National Taiwan University

臺灣大學光電所 張宏鈞教授

The pipe waveguide is promising for terahertz (THz) waveguiding owing to its low-loss feature and simple structure. In this work, modal characteristics of the leaky core modes of the pipe waveguide are investigated in the THz range. Utilizing the finite-difference frequency-domain (FDFD) mode solver, modal indices and attenuation constants of the core modes which are frequency dependent are calculated for different core diameters, cladding thicknesses, and cladding refractive indices. It is found that at certain frequencies no core modes can exist. Comparing these frequencies with the resonant frequencies of the cladding reveals that the guiding mechanism of the core modes is that of the antiresonant reflecting guiding. Calculated results also suggest that, to have a low-loss and high-bandwidth pipe waveguide, large core diameter, thin cladding thickness, and low refractive index are desired. The effect of material absorption is also examined, which shows that the attenuation constant magnitude will be increased and the increment is more significant at higher frequencies. Moreover, modal patterns are shown for the fundamental mode and the higher order modes, including modal intensity distributions and electric field vector distributions. It is observed that modal patterns of the core modes of the pipe waveguide resemble those of the guided modes of the step-index fiber. From the spectrum of the attenuation constant, it shows that the fundamental mode (HE₁₁-like) has the smallest attenuation constant and is the dominant mode for the pipe waveguide investigated. Using time-domain spectroscopy to measure the transmission spectra of PMMA pipes in collaboration with Prof. Chi-Kuang Sun, guiding mechanism of the pipe waveguides was experimentally confirmed to be that of antiresonant reflecting guiding. (Optics Express, vol. 18, no. 1, pp. 309–322, 22 January 2010.)

姓名：李正匡   指導教授：楊志忠教授

論文題目：近紅外光超螢光二極體

姓名：郭適豪   指導教授：孫啟光教授

— 資料提供：影像顯示科技知識平台 (DTKP, Display Technology Knowledge Platform) —

— 整理：林晃巖教授、陳韋仲 —

日本產業技術綜合研究所(產綜研)開發出可檢測人體動作的CNT應變感測器 

日本產業技術綜合研究所（產綜研）奈米管應用研究中心的Super Growth CNT研究小組主任研究員山田健郎，開發出了利用單層奈米碳管（CNT）的可彎曲性應變感測器。藉由黏貼在衣服與身體上，可檢測膝蓋屈伸、手指活動及呼吸發聲等人體動作。可望應用於醫療與保健領域，例如進行復健治療時，在不妨礙患者活動的情況下做各種動作的監控。此研究已刊登在學術雜誌「Nature Nanotechnology」的網路版上，未來有機會邁向元件的實際應用。

該應變感測器將已對齊的單層CNT薄膜黏貼在具伸縮性的高分子基板上，並利用CNT膜的電阻變化做應變的檢測，可檢測大到280％的應變，產綜研表示，該檢測能力相當於「原金屬製應變感測器的將近50倍」。對於150％以下的應變，該感測器具有可使用1萬次以上的耐久性。另外，該感測器對於應變的響應時間為14 ms，「在可測量100％以上大型應變感測器中，該產品的速度最快」（產綜研）。

傳統金屬應變感測器可彎曲程度較差，在測量人體動作時會有動作受限的問題（可檢測的應變為5％左右）。雖然市面上另外有採用導電性材料及高分子複合材料的應變感測器，但當發生劇烈應變時就會出現蠕變變形，「變形後恢復至可測量應變的穩定狀態需費時100 s以上的時間」（產綜研）。此次的感測器除了前面提到的可彎曲程度較高之外，與採用導電性材料及高分子複合材料的感測器相比，蠕變的恢復速度也提高了20倍以上。

產綜研奈米管應用研究中心開發出含碳純度較高的單層CNT合成法—「Super Growth法」，使單層CNT的應用開發有了進一步的發展。將垂直對齊的長尺寸單層CNT薄膜進行高密度處理，使其安置在Si晶圓上，成功製作出了高密度對齊CNT晶圓。此次透過將這種高密度對齊CNT晶圓並以任意對齊方向黏貼在可彎曲性高分子基板的任意位置，進而製作出可彎曲元件。