Yeeun Roh, Sang-Hun Lee, Boyoung Kang, Jeong Weon Wu, Byeong-Kwon Ju, and Minah Seo
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| Fig. 1 (a) Microscope picture of DSRR metamaterial. (b) THz transmittances of DSRR are shown for different polarization angles of incident THz field. Resonances are shown at 1.2THz for polarization angle 67.5° and 1.4THz for polarization angle 0°. (c) A schematic of THz transmission through DSRR covered with monosaccharide sample droplet. |
https://www.osapublishing.org/oe/abstract.cfm?uri=oe-27-13-19042
We investigate spectral responses of two different terahertz (THz) metamaterials of double split ring resonator (DSRR) and the nano slot resonator (NSR) for molecule sensing in low concentration. Two different resonant frequencies of DSRR can be controlled by polarization angle of incident THz beam. For comparison of THz optical characteristics, two NSRs were made as showing the same resonant frequencies as DSRR’s multimode. The monosaccharide molecules of glucose and galactose were detected by these two types of metamaterials matching the resonant frequencies in various concentration. NSR shows higher sensitivity in very low concentration range rather than DSRR, although the behavior was easily saturated in terms of concentration. In contrast, DSRR can cover more broad concentration range with clear linearity especially under high quality factor mode in polarization of 67.5 degree due to the Fano resonance. THz field enhancement distributions were calculated to investigate sensing performance of both sensing chips in qualitative and quantitative manner.
