Planar Plasmonic Terahertz Waveguides for Sensor Applications

We investigate sensing capabilities of a planar plasmonic THz waveguide. The waveguide is comprised of one dimensional array of periodically arranged sub wavelength scale corrugations in the form of rectangular dimples in order to ensure the plasmonic response. The THz waveguide transmission is observed for polyimide (as thin film) substance filling the dimples. The refractive index of the polyimide film is varied to examine various sensing parameters such as frequency shift, sensitivity and Figure of Merit (FoM) of the fundamental plasmonic resonance supported by the waveguide. In efforts to improve sensing characteristics, we also examine sensing capabilities of a plasmonic waveguide having V shaped corrugations and compare results with that of rectangular dimples. The proposed study could be significant in developing new terahertz sensors with improved sensitivity utilizing the plasmonic waveguides.





References:
[1] Mookherjea, S., et al., Localization in silicon nanophotonic slow-light waveguides. Nature Photonics, 2008. 2(2): p. 90-93.
[2] Scullion, M.G., et al., Enhancement of optical forces using slow light in a photonic crystal waveguide. Optica, 2015. 2(9): p. 816-821.
[3] Mendis, R., et al., A tunable universal terahertz filter using artificial dielectrics based on parallel-plate waveguides. Applied physics letters, 2010. 97(13): p. 131106.
[4] Correas-Serrano, D., et al., Graphene-based plasmonic tunable low-pass filters in the terahertz band. IEEE Transactions on Nanotechnology, 2014. 13(6): p. 1145-1153.
[5] Mendis, R., et al., Terahertz microfluidic sensor based on a parallel-plate waveguide resonant cavity. Applied Physics Letters, 2009. 95(17): p. 171113.
[6] Shibayama, J., et al., Surface plasmon resonance waveguide sensor in the terahertz regime. Journal of Lightwave Technology, 2016. 34(10): p. 2518-2525.
[7] Islam, M., et al., Role of Resonance Modes on Terahertz Metamaterials based Thin Film Sensors. Scientific Reports, 2017. 7.
[8] McKinney, R.W., et al., Focused terahertz waves generated by a phase velocity gradient in a parallel-plate waveguide. Optics express, 2015. 23(21): p. 27947-27952.
[9] Martin-Cano, D., et al., Waveguided spoof surface plasmons with deep-subwavelength lateral confinement. Optics letters, 2011. 36(23): p. 4635-4637.
[10] Liu, S., O. Mitrofanov, and A. Nahata, Near-field terahertz imaging using sub-wavelength apertures without cutoff. Optics express, 2016. 24(3): p. 2728-2736.
[11] Cao, H. and A. Nahata, Coupling of terahertz pulses onto a single metal wire waveguide using milled grooves. Optics express, 2005. 13(18): p. 7028-7034.
[12] Chen, D. and H. Chen, A novel low-loss Terahertz waveguide: Polymer tube. Optics express, 2010. 18(4): p. 3762-3767.
[13] Chen, L., et al., Controllable multiband terahertz notch filter based on a parallel plate waveguide with a single deep groove. Optics letters, 2014. 39(15): p. 4541-4544.
[14] Khromova, I., A. Andryieuski, and A. Lavrinenko, Ultrasensitive terahertz/infrared waveguide modulators based on multilayer graphene metamaterials. Laser & Photonics Reviews, 2014. 8(6): p. 916-923.
[15] Xiao, B., et al., A terahertz modulator based on graphene plasmonic waveguide. IEEE Photonics Technology Letters, 2015. 27(20): p. 2190-2192.
[16] Baba, T., et al., Large delay-bandwidth product and tuning of slow light pulse in photonic crystal coupled waveguide. Optics express, 2008. 16(12): p. 9245-9253.
[17] Hao, R., et al., Improved slow light capacity in graphene-based waveguide. Scientific reports, 2015. 5.
[18] Hu, J., S. Xie, and Y. Zhang, Micromachined terahertz rectangular waveguide bandpass filter on silicon-substrate. IEEE microwave and wireless components letters, 2012. 22(12): p. 636-638.
[19] Islam, M., et al., Terahertz guided mode properties in an internally corrugated plasmonic waveguide. Journal of Applied Physics, 2017. 122(5): p. 053105.
[20] Kleine-Ostmann, T. and T. Nagatsuma, A review on terahertz communications research. Journal of Infrared, Millimeter, and Terahertz Waves, 2011. 32(2): p. 143-171.
[21] Song, S., et al., Narrow-linewidth and high-transmission terahertz bandpass filtering by metallic gratings. IEEE Transactions on Terahertz Science and Technology, 2015. 5(1): p. 131-136.
[22] Tao, J., et al., Tunable subwavelength terahertz plasmonic stub waveguide filters. IEEE Transactions on Nanotechnology, 2013. 12(6): p. 1191-1197.
[23] Williams, C.R., et al., Highly confined guiding of terahertz surface plasmon polaritons on structured metal surfaces. Nature Photonics, 2008. 2(3): p. 175-179.
[24] Gagan, K., et al., Planar plasmonic terahertz waveguides based on periodically corrugated metal films. New Journal of Physics, 2011. 13(3): p. 033024.
[25] Zhu, W., A. Agrawal, and A. Nahata, Planar plasmonic terahertz guided-wave devices. Optics express, 2008. 16(9): p. 6216-6226.
[26] Pandey, S., B. Gupta, and A. Nahata, Terahertz plasmonic waveguides created via 3D printing. Optics express, 2013. 21(21): p. 24422-24430.
[27] Kumar, G., et al., Terahertz surface plasmon waveguide based on a one-dimensional array of silicon pillars. New Journal of Physics, 2013. 15(8): p. 085031.
[28] Islam, M. and G. Kumar, Terahertz surface plasmons propagation through periodically tilted pillars and control on directional properties. Journal of Physics D: Applied Physics, 2016. 49(43): p. 435104.
[29] Wood, J. J., et al., Spoof plasmon polaritons in slanted geometries. Physical Review B, 2012. 85(7): p. 075441.
[30] Li, S., et al., Terahertz surface plasmon polaritons on a semiconductor surface structured with periodic V-grooves. Optics express, 2013. 21(6): p. 7041-7049.
[31] Nagai, M., et al., Achromatic wave plate in THz frequency region based on parallel metal plate waveguides with a pillar array. Optics express, 2015. 23(4): p. 4641-4649.
[32] Mittendorff, M., S. Li, and T.E. Murphy, Graphene-based waveguide-integrated terahertz modulator. ACS Photonics, 2017. 4(2): p. 316-321.