volume | PIER Journals

Abstract

In this study, transmission characteristics of a novel THz wire waveguide --- conical metal wire with dielectric coating at 0.1-1 THz are studied. The investigation results show that the coated conical wire with virtually low attenuation and high energy concentration is a promising candidate as THz transmission medium. The calculation results agree well with that of simulation such as high frequency structure simulation (HFSS), which is based on the finite element method. In this paper, a novel transition from a coaxial line to the coated conical metal wire is designed. Although coaxial probe excitation has been used in microstrip lines and rectangular waveguides in microwave, millimeter-wave frequency domains, the present study shows that it is also an effective method to excite conical wire at THz frequency. As shown in the investigation results, the return loss of coax-conical wire transition is better than 20 dB from 0.1-0.5 THz, and the insertion loss is as low as 1 dB (the total length is 15 mm). It is a promising THz transition structure.

1. Siegel, P. H., "Terahertz technology in biology and medicine," IEEE Trans. Microwave Theory Tech., Vol. 52, 2438-2447, 2004.
doi:10.1109/TMTT.2004.835916

2. Nagel, M., P. Haring Bolivar, M. Brucherseifer, and H. Kurz, "Integrated THz technology for label-free genetic diagnostics," Appl. Phys. Lett., Vol. 80, 154-156, 2002.
doi:10.1063/1.1428619

3. Schmuttenmaer, C. A., "Exploring dynamics in the far-Infrared with terahertz spectroscopy," Chem. Rev., Vol. 104, 1759-1779, 2004.
doi:10.1021/cr020685g

4. Ogawa, Y., S. Hayashi, C. Otani, and K. Kawase, "Terahertz sensing for ensuring the safety and security," PIERS Online, Vol. 4, No. 3, 396-400, 2008.
doi:10.2529/PIERS070831051620

5. Zhang, X. C., "Terahertz wave imaging: Horizons and hurdles," Phys. Med. Biol., Vol. 47, 3667-3677, 2002.
doi:10.1088/0031-9155/47/21/301

6. Awad, M. M. and R. A. Cheville, "Transmission terahertz waveguide-based imaging below the diffraction limit," Appl. Phys. Lett., Vol. 86, 1-3, 2005.

7. McGowan, R. W., G. Gallot, and D. Grischkowsky, "Propagation of ultrawideband short pulses of terahertz radiation through submillimeter-diameter circular waveguides," Opt. Lett., Vol. 24, No. 20, 1431-1433, 1999.
doi:10.1364/OL.24.001431

8. Gallot, G., S. P. Jamison, R. W. McGowan, and D. Grischkowsky, "Terahertz waveguides," J. Opt. Soc. Am. B, Vol. 17, No. 5, 851-863, 2000.
doi:10.1364/JOSAB.17.000851

9. Zhou, Y. and S. Lucyszyn, "HFSS^TM modeling anomalies with THz metal-pipe rectangular waveguide structures at room temperature," PIERS Online, Vol. 5, No. 3, 201-211, 2009.
doi:10.2529/PIERS080907072308

10. Lucyszyn, S. and Y. Zhou, "Engineering approach to modeling frequency dispersion within normal metals at room temperature for THz applications," Progress In Electromagnetics Research, Vol. 101, 257-275, 2010.
doi:10.2528/PIER09121506

11. Mendis, R. and D. Grischkowsky, "Plastic ribbon THz waveguides," J. Appl. Phys, Vol. 88, 4449-4451, 2000.
doi:10.1063/1.1310179

12. Jamison, S. P., R. W. McGown, and D. Grischkowsky, "Single-mode waveguide propagation and reshaping of sub-ps terahertz pulses in sapphire fiber," Appl. Phys. Lett., Vol. 76, 1987-1989, 2000.
doi:10.1063/1.126231

13. Ponseca Jr., C. S., R. Pobre, E. Estacio, N. Sarukura, et al. "Transmission of terahertz radiation using a microstructured polymer optical fiber," Opt. Lett., Vol. 33, 902-904, 2008.
doi:10.1364/OL.33.000902

14. Han, H., H. Park, M. Cho, and J. Kim, "Terahertz pulse propagation in a plastic photonic crystal fiber," Appl. Phys. Lett., Vol. 80, 2634-2636, 2002.
doi:10.1063/1.1468897

15. Chen, D. and H. Chen, "Highly birefringent low-Loss terahertz waveguide: Elliptical polymer tube," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 11-12, 1553-1562, 2010.
doi:10.1163/156939310792149623

16. Harrington, J. A., R. George, P. Pedersen, and E. Mueller, "Hollow polycarbonate waveguides with inner Cu coatings for delivery of terahertz radiation," Opt. Express, Vol. 12, 5263-5268, 2004.
doi:10.1364/OPEX.12.005263

17. He, X. Y. and H. X. Lu, "Investigation on propagation properties of terahertz waveguide hollow plastic fiber," Opt. Fiber Technol., Vol. 12, 145-148, 2009.
doi:10.1016/j.yofte.2008.09.003

18. Matsuura, Y. and E. Takeda, "Hollow optical fibers loaded with an inner dielectric film for terahertz broadband spectroscopy," J. Opt. Soc. Am. B, Vol. 25, 1949-1954, 2008.
doi:10.1364/JOSAB.25.001949

19. Mendis, R. and D. Grischkowsky, "Undistorted guided-wave propagation of subpicosecond terahertz pulses," Opt. Lett., Vol. 26, 846-848, 2001.
doi:10.1364/OL.26.000846

20. Coleman, S. and D. Grischkowsky, "A THz transverse electro-magnetic mode two-dimensional interconnect layer incorporating quasi-optics," Appl. Phys. Lett., Vol. 83, 3656-3658, 2003.
doi:10.1063/1.1624474

21. Zhang, H., S. Y. Tan, and H. S. Tan, "Experimental investigation on flanged parallel-plate dielectric waveguide probe for detection of conductive inclusions in lossy dielectric medium," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 5-6, 681-693, 2010.
doi:10.1163/156939310791036287

22. Cheng, Q. and T. J. Cui, "Guided modes and continuous modes in parallel-plate waveguides excited by a line source," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 12, 1577-1587, 2007.

23. Wang, K. and M. Mittleman, "Metal wires for terahertz wave guiding," Nature, Vol. 432, 376-379, 2004.
doi:10.1038/nature03040

24. McGowan, R. W., G. Gallot, and D. Grischkowsky, "Propagation of ultra wideband short pulses of THz radiation through submillimeterdiameter circular waveguides," Opt. Lett., Vol. 24, 1431-1433, 1999.
doi:10.1364/OL.24.001431

25. Wang, K. L. and D. M. Mittleman, "Dispersion of surface plasmon polaritons on metal wires in the terahertz frequency range," Phys. Rev. Lett., Vol. 96, 157401, 2006.
doi:10.1103/PhysRevLett.96.157401

26. Van der Valk, N. C. J. and P. C. M. Planken, "Effect of a dielectric coating on terahertz surface plasmon polaritons on metal wires," Appl. Phys. Lett., Vol. 87, 071106, 2005.
doi:10.1063/1.2011773

27. Walther, M., M. R. Freeman, and F. A. Hegmann, "Metal-wire terahertz time-domain spectroscopy," Appl. Phys. Lett., Vol. 87, 261107, 2005.
doi:10.1063/1.2158025

28. Hagmann , M. J., "Isolated carbon nanotubes as high-impedance transmission lines for microwave through terahertz frequencies," IEEE Trans. Nanotech., Vol. 4, 289-296, 2005.
doi:10.1109/TNANO.2004.842040

29. Jeon, T.-I., J. Zhang, and D. Grischkowsky, "THz Sommerfeld wave propagation on a single metal wire," Appl. Phys. Lett., Vol. 86, 161904, 2005.
doi:10.1063/1.1904718

30. Ji, Y. B., E. S. Lee, J. S. Seok, T.-I. Jeon, M. H. Kwak, and K.-Y. Kwang, "Guidance properties of metal wire waveguide by terahertz pulse propagation," J. Korean Phys. Soc., Vol. 50, 1238-1242, 2007.
doi:10.3938/jkps.50.1238

31. Yang, F., J. R. Sambles, and G. W. Bradberry, "Long-range surface modes supported by thin films," Phys. Rev. B, Vol. 44, 5855-5872, 1991.
doi:10.1103/PhysRevB.44.5855

32. Goubau , G., "Surface waves and their application to transmission lines," J. Appl. Phys., Vol. 21, 1119-1128, 1950.
doi:10.1063/1.1699553

33. Deibel, J. A., N. Berndsen, K. Wang, D. M. Mittleman, N. C. J. van der Valk, and P. C. M. Planken, "Frequency-dependent radiation patterns emitted by THz plasmons on finite length cylindrical metal wires," Opt. Express, Vol. 14, 8772-8778, 2006.
doi:10.1364/OE.14.008772

34. Smorenburg, P. W., W. P. E. M. O. Root, and O. J. Luiten, "Direct generation of terahertz surface plasmon polaritons on a wire using electron bunches," Phys. Rev. B , Vol. 78, 115415, 2008.
doi:10.1103/PhysRevB.78.115415

35. Stockman, M. I., "Nanofocusing of optical energy in tapered plasmonic waveguides," Phys. Rev. Lett., Vol. 93, 137404, 2004.
doi:10.1103/PhysRevLett.93.137404

36. Liang, H., S. Ruan, and M. Zhang, "Terahertz surface wave propagation and focusing on conical metal wires," Opt. Express, Vol. 16, 18241-18248, 2008.
doi:10.1364/OE.16.018241

37. Garcia-Vidal "Terahertz surface plasmon-polariton propagation and focusing on periodically corrugated metal wires," Phys. Rev. Lett., Vol. 97, 176805, 2006.

38. Vernon, K. C., D. K. Gramotnev, and D. F. P. Pile, "Adiabatic nanofocusing of plasmons by a sharp metal wedge on a dielectric substrate," J. Appl. Phys., Vol. 101, 104312, 2007.
doi:10.1063/1.2732699

39. Awad, M., M. Nagel, and H. Kurz, "Tapered Sommerfeld wire terahertz near-field imaging," Appl. Phys. Lett., Vol. 94, 051107, 2009.
doi:10.1063/1.3078278

40. Issa, N. A. and R. Guckenberger, "Fluorescence near metal tips: The roles of energy transfer and surface plasmon polaritons," Opt. Express, Vol. 15, 12131-12144, 2007.
doi:10.1364/OE.15.012131

41. King, M. J. and J. C. Wiltse, "Surface-wave propagation on coated and uncoated metal wires at millimeter wavelengths," IRE Trans. Antennas Propag., Vol. 10, 246-254, 1962.
doi:10.1109/TAP.1962.1137859

42. Pozar, D. M., Microwave Engineering, Whily, New York, 2004.

43. Ji , Y. B., E. S. Lee, J. S. Jang, and T.-I. Jeon, "Enhancement of the detection of THz Sommerfeld wave using a conical wire waveguide," Opt. Express, Vol. 16, 271-278, 2008.
doi:10.1364/OE.16.000271

44. Ye, L. F., R. M. Xu, Z. H. Wang, and W. G. Lin, "A novel broadband coaxial probe to parallel plate dielectric waveguide transition at THz frequency," Opt. Express, Vol. 18, 21725-21731, 2010.
doi:10.1364/OE.18.021725

Dr. Zhihui Wang

Dr. Yong Zhang

Professor Rui-Min Xu

Professor Weigan Lin