Acta Chimica Sinica ›› 2013, Vol. 71 ›› Issue (9): 1275-1280.DOI: 10.6023/A13040418 Previous Articles     Next Articles



吕江涛, 杨琳娟, 李志刚, 魏永涛, 张宝健, 梁丽勤, 王凤文, 司光远   

  1. 东北大学 信息科学与工程学院 沈阳 110819
  • 投稿日期:2013-04-17 发布日期:2013-06-13
  • 通讯作者: 司光远,;Tel.:13603239536
  • 基金资助:


Resonance Tuning in Plasmonic Nanorods for Enhanced Infrared Spectrum Detecting

Lv Jiangtao, Yang Linjuan, Li Zhigang, Wei Yongtao, Zhang Baojian, Liang Liqin, Wang Fengwen, Si Guangyuan   

  1. College of Information Science and Engineering, Northeastern University, Shenyang 110819
  • Received:2013-04-17 Published:2013-06-13
  • Supported by:

    Project supported by the NEU Internal Funding (No. XNB201302), Natural Science Foundation of Hebei Province (No. A2013501049) and Fundamental Research Funds for the Central Universities (No. N120323014).

Surface plasmons are electromagnetic waves propagating along metallic-dielectric interfaces and they have drawn considerable attention in the past ten years since extraordinary optical transmission (EOT) phenomenon was first reported. They can take different forms, from propagating waves to localized electron oscillations. Owning to their peculiar optical properties and particular capability of manipulating light at sub-wavelength scales, a wide range of practical applications have been enabled. Since the near-field of electromagnetic waves can be enhanced dramatically using plasmonic structures with different designs, surface plasmon based waveguides are of special importance to develop sensors and detectors with ultra-high sensitivity and figure of merit. Research on surface plasmons covers a broad scope with potential applications ranging from waveguiding to sensing. But plasmon assisted infrared detectors are rarely reported especially the ones working under near infrared (NIR) range. Tuning of surface plasmons in the NIR range is critical and essential to develop nanophotonic devices like modulators and sensors. Recently, plasmon assisted devices have drawn increasing interest. In this work, we show the combination of plasmonic nanorod arrays with NIR spectrum detection. Using electron-beam lithography (EBL) and ion milling techniques, gold (Au) nanorod arrays with varying periodicities were fabricated on transparent quartz substrates. By collecting and investigating the transmittance spectra of nanorods, precise tuning of localized surface plasmon resonance (LSPR) in the infrared range can be realized by changing the periodicity of nanorods. Experimental results show that the resonant wavelength of LSPR dips redshifts with increasing array periodicity and the distance of shift can be accurately controlled. Simulations show qualitative agreement with experimental results. The influence of waveguide sidewall on device performance is also discussed in detail. In addition, optical properties of nanorods with different heights were compared and investigated. By combining silver (Ag) nanorod structures with attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy technique, the absorbance of glucose can be effectively enhanced. Therefore, periodical nanorod arrays can significantly enhance the near field intensity, enabling extensive applications in signal sensing and detecting.

Key words: nanorods, surface plasmon resonance, tuning, FTIR, spectrum enhancement