Abstract

We developed a metal hollow waveguide as a flexible delivery medium of terahertz waves. Theoretical evaluation shows that a metal waveguide mainly supports TE modes and that the TE11 mode shows a high coupling coefficient to linearly polarized light. Also the TE11 mode brings less mode conversion to high-order modes than the TE01 mode giving the lowest loss. We measured transmission losses in the terahertz region of hollow waveguides with inner silver coating; the losses were 7.58dBm at the wavelengths from 190250μm for waveguides with an inner diameter of 1mm. These losses coincide well with theoretical ones, and this shows that in these waveguides, the TE11 mode is dominant when a linearly polarized beam is launched into them. The waveguides are flexible because we use a thin-wall glass capillary as the base tubing. Our experiment revealed low additional losses due to bending even when complicated bends were applied to the waveguides. The metal-coated hollow fiber with an inner diameter of 1mm is sufficiently small and flexible for use in endoscopic applications.

© 2007 Optical Society of America

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References

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]

2006

2005

2004

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

K. Wang and D. M. Mittleman, 'Metal wires for terahertz waveguiding,' Nature 432, 376-379 (2004).
[CrossRef] [PubMed]

J. A. Harrington, R. George, P. Pedersen, and E. Mueller, 'Hollow polycarbonate waveguides with inner Cu coatings for delivery of terahertz radiation,' Opt. Express 12, 5263-5268 (2004).
[CrossRef] [PubMed]

2003

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

2002

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

K. Kawase, J. Shikata, and H. Ito, 'Terahertz wave parametric source,' J. Phys. D 35, R1-R14 (2002).
[CrossRef]

2001

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

2000

S. P. Jamison, R. W. McGowan, and D. Grischkowsky, 'Single-mode waveguide propagation and reshaping of sub-ps terahertz pulse in sapphire fibers,' Appl. Phys. Lett. 76, 1987-1989 (2000).
[CrossRef]

G. Gallot, S. P. Jamison, R. W. McGowan, and D. Grischkowsky, 'Terahertz waveguides,' J. Opt. Soc. Am. B 17, 851-863 (2000).
[CrossRef]

1999

1988

1987

1985

M. Miyagi, 'Waveguide-loss evaluation in circular hollow waveguides and its ray-optical treatment,' J. Lightwave Technol. LT-3, 303-307 (1985).
[CrossRef]

1984

M. Miyagi and S. Kawakami, 'Design theory of dielectric-coated circular metallic waveguides for infrared transmission,' J. Lightwave Technol. LT-2, 116-126 (1984).
[CrossRef]

1983

Abe, Y.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Akiyama, T.

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

Alexander, R. W.

Bell, R. J.

Bell, R. R.

Bell, S. E.

Cho, M.

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

Deibel, J. A.

Escarra, M. D.

Gallot, G.

George, R.

Goto, M.

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Grischkowsky, D.

Han, H.

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

Harrington, J. A.

Hidaka, T.

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

T. Hidaka, H. Minamide, and H. Ito, 'Bent-angle dependency of ferroelectric PVDF cladding THz waveguides,' in Proceedings of the 11th IEEE International Conference on Terahertz Electronics (IEEE, 2003), p. 76.

Ito, H.

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

K. Kawase, J. Shikata, and H. Ito, 'Terahertz wave parametric source,' J. Phys. D 35, R1-R14 (2002).
[CrossRef]

T. Hidaka, H. Minamide, and H. Ito, 'Bent-angle dependency of ferroelectric PVDF cladding THz waveguides,' in Proceedings of the 11th IEEE International Conference on Terahertz Electronics (IEEE, 2003), p. 76.

Jamison, S. P.

G. Gallot, S. P. Jamison, R. W. McGowan, and D. Grischkowsky, 'Terahertz waveguides,' J. Opt. Soc. Am. B 17, 851-863 (2000).
[CrossRef]

S. P. Jamison, R. W. McGowan, and D. Grischkowsky, 'Single-mode waveguide propagation and reshaping of sub-ps terahertz pulse in sapphire fibers,' Appl. Phys. Lett. 76, 1987-1989 (2000).
[CrossRef]

Kawakami, S.

M. Miyagi and S. Kawakami, 'Design theory of dielectric-coated circular metallic waveguides for infrared transmission,' J. Lightwave Technol. LT-2, 116-126 (1984).
[CrossRef]

Kawase, K.

K. Kawase, J. Shikata, and H. Ito, 'Terahertz wave parametric source,' J. Phys. D 35, R1-R14 (2002).
[CrossRef]

Kim, J.

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

Long, L. L.

Love, J. D.

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman and Hall, 1983), Chap. 27.

Maeta, S.

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

Matsuura, Y.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

McGowan, R. W.

Minamide, H.

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

T. Hidaka, H. Minamide, and H. Ito, 'Bent-angle dependency of ferroelectric PVDF cladding THz waveguides,' in Proceedings of the 11th IEEE International Conference on Terahertz Electronics (IEEE, 2003), p. 76.

Mittleman, D. M.

Miyagi, M.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

M. Miyagi, 'Waveguide-loss evaluation in circular hollow waveguides and its ray-optical treatment,' J. Lightwave Technol. LT-3, 303-307 (1985).
[CrossRef]

M. Miyagi and S. Kawakami, 'Design theory of dielectric-coated circular metallic waveguides for infrared transmission,' J. Lightwave Technol. LT-2, 116-126 (1984).
[CrossRef]

Mohri, S.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Mueller, E.

Newquist, L. A.

Ono, S.

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Ordal, M. A.

Palik, E. D.

E. D. Palik, ed., Handbook of Optical Constants of Solids (Academic, 1985).

Park, H.

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

Pedersen, P.

Quema, A.

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Querry, M. R.

Sarukura, N.

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Shi, Y.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Shikata, J.

K. Kawase, J. Shikata, and H. Ito, 'Terahertz wave parametric source,' J. Phys. D 35, R1-R14 (2002).
[CrossRef]

Snyder, A. W.

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman and Hall, 1983), Chap. 27.

Takada, G.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Takahashi, H.

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Wang, K.

Ward, C. A.

Yaegashi, M.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

S. P. Jamison, R. W. McGowan, and D. Grischkowsky, 'Single-mode waveguide propagation and reshaping of sub-ps terahertz pulse in sapphire fibers,' Appl. Phys. Lett. 76, 1987-1989 (2000).
[CrossRef]

H. Han, H. Park, M. Cho, and J. Kim, 'Terahertz pulse propagation in a plastic photonic crystal fiber,' Appl. Phys. Lett. 80, 2634-2636 (2002).
[CrossRef]

J. Lightwave Technol.

M. Miyagi and S. Kawakami, 'Design theory of dielectric-coated circular metallic waveguides for infrared transmission,' J. Lightwave Technol. LT-2, 116-126 (1984).
[CrossRef]

M. Miyagi, 'Waveguide-loss evaluation in circular hollow waveguides and its ray-optical treatment,' J. Lightwave Technol. LT-3, 303-307 (1985).
[CrossRef]

J. Opt. Soc. Am. B

J. Phys. D

K. Kawase, J. Shikata, and H. Ito, 'Terahertz wave parametric source,' J. Phys. D 35, R1-R14 (2002).
[CrossRef]

Jpn. J. Appl. Phys., Part 2

M. Goto, A. Quema, H. Takahashi, S. Ono, and N. Sarukura, 'Teflon photonic crystal fiber as terahertz waveguides,' Jpn. J. Appl. Phys., Part 2 43, L317-L319 (2004).
[CrossRef]

Nature

K. Wang and D. M. Mittleman, 'Metal wires for terahertz waveguiding,' Nature 432, 376-379 (2004).
[CrossRef] [PubMed]

Opt. Express

Opt. Laser Technol.

Y. Matsuura, Y. Shi, Y. Abe, M. Yaegashi, G. Takada, S. Mohri, and M. Miyagi, 'Infrared-laser delivery system based on polymer-coated hollow fibers,' Opt. Laser Technol. 33, 279-283 (2001).
[CrossRef]

Opt. Lett.

Proc. SPIE

T. Hidaka, H. Minamide, H. Ito, S. Maeta, and T. Akiyama, 'Ferroelectric PVDF cladding terahertz waveguide,' in Optical Information, Data Processing and Storage, and Laser Communication Technologies J.-P. Goedgebuer, N. N. Rozanov, S. K. Turitsyn, A. S. Akhmanov, and V. Y. Panchenko, eds., Proc. SPIE 5135, 70-77 (2003).
[CrossRef]

Other

T. Hidaka, H. Minamide, and H. Ito, 'Bent-angle dependency of ferroelectric PVDF cladding THz waveguides,' in Proceedings of the 11th IEEE International Conference on Terahertz Electronics (IEEE, 2003), p. 76.

E. D. Palik, ed., Handbook of Optical Constants of Solids (Academic, 1985).

C.G.Montgomery, R.H.Dicke, and E.M.Purcell, eds., Principles of Microwave Circuits (Peter Peregrinus, 1987), Chap. 2.
[CrossRef]

A. W. Snyder and J. D. Love, Optical Waveguide Theory (Chapman and Hall, 1983), Chap. 27.

J. A. Harrington, Infrared Fiber Optics and Their Applications (SPIE, 2004).
[CrossRef]

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Figures (11)

Fig. 1
Fig. 1

Calculated n ( n 2 + k 2 ) of various metals as a function of wavelength.

Fig. 2
Fig. 2

Theoretical attenuations of low-order TE and TM modes in gold hollow waveguides with an inner diameter of 1.0 mm .

Fig. 3
Fig. 3

Lines of current flow (solid curves) and magnetic lines (dotted curves) of low-order TE and TM modes in circular metal waveguides.

Fig. 4
Fig. 4

Calculated coupling coefficients of TE 1 q and TM 1 q modes for a Gaussian input beam having a waist size of 2 w 0 .

Fig. 5
Fig. 5

Measured loss spectra of hollow waveguides in visible to near-infrared regions. The waveguides have an inner coating of silver deposited under the different conditions listed in Table 1. The waveguides are 1 mm in diameter and 60 cm in length.

Fig. 6
Fig. 6

Measured loss spectra of hollow waveguides in the terahertz region. The waveguides have an inner coating of silver deposited under the different conditions listed in Table 1. The waveguides are 1 mm in diameter and 60 cm in length.

Fig. 7
Fig. 7

Experimental setup for measurement of attenuation losses of hollow waveguides in the terahertz region.

Fig. 8
Fig. 8

Measured attenuation of silver-coated waveguides in the terahertz region. The inner diameter of the waveguides is 1 mm . Theoretical losses are also shown for comparison.

Fig. 9
Fig. 9

Attenuation of silver-coated waveguides with different diameters measured at a wavelength of 200 μ m . Theoretical attenuation of the TE 11 mode is also shown for comparison.

Fig. 10
Fig. 10

Measured losses of silver-coated waveguides bent at two different radii. The wavelength is 200 μ m and the waveguides have an inner diameter of 1 mm and length of 60 cm .

Fig. 11
Fig. 11

Measured loss spectra of silver-coated waveguides bent in three different shapes, loop (crosses), S shape (open circles), and screw (closed circles). The waveguides have an inner diameter of 2 mm and length of 1 m .

Tables (1)

Tables Icon

Table 1 Deposition Conditions of Waveguide Samples

Equations (7)

Equations on this page are rendered with MathJax. Learn more.

Z TE = n 0 k 0 ω μ 0 E y H z , Y TM = ω μ 0 n 0 k 0 H y E z ,
Z TE = 1 ν 2 1 , Y TM = ν 2 ν 2 1 .
α = u 2 ( n 0 k 0 ) 2 T 3 n n 2 + k 2 , TE 0 q mode ,
α = 1 T n n 2 + k 2 , TM p q mode ,
α = n u 4 ( u 2 p 2 ) n n 2 + k 2 ( 1 k 0 2 T 3 + p 2 u 4 T ) , TE p q mode .
η = β n 0 k 0 ( w 0 T ) 2 exp [ u 2 2 ( w 0 t ) 2 ] × { 1 ( 1 1 u 2 ) J 1 2 ( u ) , TE 1 q mode 1 J 0 2 ( u ) , TM 1 q mode ,
β = ( n 0 k 0 ) 2 ( u T ) 2 .

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