Dielectric waveguide, terahertz circuit and terahertz integrated circuit
An UC dielectric waveguide of the embodiments includes: a dielectric substance wiring propagating a terahertz wave; and a medium disposed around the dielectric substance wiring and having a large refractive index difference with respect to the dielectric substance wiring. A THz circuit of the embodiments includes a dielectric substance THz circuit connected between a first and second UC dielectric waveguides. The dielectric substance THZ circuit includes a circuit including a linear-shaped UC dielectric waveguide, a bent-shaped UC dielectric waveguide, and a Y-coupled branch circuit. There are included a first holding unit holding the first UC dielectric waveguide and a second holding unit holding the second UC dielectric waveguide. The THZ circuit of the embodiments may include a 2×2 evanescent coupler. Provided is a THz circuit having mechanical strength obtained by applying the UC dielectric waveguide having high confinement and transmission efficiencies of THz waves with a simple structure.
1 . A dielectric waveguide comprising:
a dielectric substance wiring configured to propagate a terahertz wave;
a medium disposed around the dielectric substance wiring, the medium having a large refractive index difference with respect to the dielectric substance wiring;
a holding unit configured to hold the dielectric substance wiring; and
a low-refractive index cladding layer disposed between the holding unit and the dielectric substance wiring, wherein
the terahertz wave is confined within the dielectric substance wiring.
2 . The dielectric waveguide according to claim 1 , wherein
the medium comprises one selected from the group consisting of air, nitrogen, xenon, and helium.
3 . The dielectric waveguide according to claim 1 , wherein
the dielectric substance wiring comprises
a first unclad dielectric waveguide disposed at one end portion, and
a second unclad dielectric waveguide disposed at the other end portion.
4 . The dielectric waveguide according to claim 3 , further comprising
a dielectric substance terahertz circuit disposed between the first unclad dielectric waveguide and the second unclad dielectric waveguide.
5 . The dielectric waveguide according to claim 4 , wherein
the dielectric substance terahertz circuit comprises a circuit composed of a dielectric.
6 . The dielectric waveguide according to claim 4 , wherein
the dielectric substance terahertz circuit comprises a circuit including an unclad dielectric waveguide.
7 . The dielectric waveguide according to claim 4 , wherein
the dielectric substance terahertz circuit comprises a circuit obtained by combining a circuit including an unclad dielectric waveguide and a circuit including an effective-medium-cladded dielectric waveguide.
8 . The dielectric waveguide according to claim 4 , wherein
the dielectric substance terahertz circuit comprises a circuit obtained by combining a circuit including an unclad dielectric waveguide and a circuit including a photonic crystal waveguide.
9 . The dielectric waveguide according to claim 4 , wherein
the dielectric substance terahertz circuit comprises a circuit obtained by combining a circuit including an unclad dielectric waveguide, a circuit including an effective-medium-cladded dielectric waveguide, and a circuit including a photonic crystal waveguide.
10 . The dielectric waveguide according to claim 1 , further comprising:
a package substrate; and
a package disposed on the package substrate, the package configured to seal the dielectric substance wiring, wherein
the dielectric substance wiring is disposed above the package substrate via the medium.
11 . The dielectric waveguide according to claim 1 , wherein
the dielectric substance wiring comprises any one of materials selected from the group consisting of silicon (Si), GaAs, InP, GaN, GalnAsP/InP, GalnAs/GaAs, GaAlAs/GaAs, GalInNAs/GaAs, GaAlInAs/InP, AlGaInP/GaAs, GaInN/GaN, plastic, glass, epoxy resin, and poly-tetrafluoroethylene.
12 . A terahertz circuit comprising:
a first unclad dielectric waveguide;
a second unclad dielectric waveguide;
a dielectric substance terahertz circuit connected between the first unclad dielectric waveguide and the second unclad dielectric waveguide;
a first holding unit configured to hold the first unclad dielectric waveguide;
a second holding unit configured to hold the second unclad dielectric waveguide;
a first low-refractive index cladding layer disposed between the first holding unit and the first unclad dielectric waveguide; and
a second low-refractive index cladding layer disposed between the second holding unit and the second unclad dielectric waveguide.
13 . The terahertz circuit according to claim 12 , wherein
the dielectric substance terahertz circuit comprises a circuit including a linear-shaped unclad dielectric waveguide.
14 . The terahertz circuit according to claim 12 , wherein
the dielectric substance terahertz circuit comprising a circuit including a bent-shaped unclad dielectric waveguide.
15 . The terahertz circuit according to claim 12 , wherein
the dielectric substance terahertz circuit comprises a circuit including a Y-coupled branch circuit.
16 . The terahertz circuit according to claim 15 , wherein
the Y-coupled branch circuit comprises a circuit including unclad dielectric waveguides having a symmetrically arranged circular bend structure.
17 . The terahertz circuit according to claim 12 , wherein
the dielectric substance terahertz circuit comprises an unclad dielectric waveguide having a first wiring width at a first bent portion, and a second wiring width wider than the first wiring width at a second portion different from the first bent portion.
18 . A terahertz integrated circuit comprising:
a first unclad dielectric waveguide;
a second unclad dielectric waveguide capable of evanescent coupling to the first unclad dielectric waveguide; and
a holding unit configured to hold the first unclad dielectric waveguide and the second unclad dielectric waveguide, wherein
the first unclad dielectric waveguide has a first wiring width at a first bent portion, and a second wiring width wider than the first wiring width at a portion different from the first bent portion, wherein
the second unclad dielectric waveguide comprises periodic lattice points in which a size and a period of holes are gradually increased.