US 11,747,558 B2
Photonic crystal optical resonator
Eiichi Kuramochi, Tokyo (JP); Shota Kita, Tokyo (JP); Hideaki Taniyama, Tokyo (JP); Akihiko Shinya, Tokyo (JP); and Masaya Notomi, Tokyo (JP)
Assigned to Nippon Telegraph and Telephone Corporation, Tokyo (JP)
Appl. No. 17/431,013
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Feb. 4, 2020, PCT No. PCT/JP2020/004040
§ 371(c)(1), (2) Date Aug. 13, 2021,
PCT Pub. No. WO2020/170795, PCT Pub. Date Aug. 27, 2020.
Claims priority of application No. 2019-026454 (JP), filed on Feb. 18, 2019.
Prior Publication US 2022/0075116 A1, Mar. 10, 2022
Int. Cl. G02B 6/122 (2006.01); G02B 6/13 (2006.01)
CPC G02B 6/1225 (2013.01) [G02B 6/13 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A photonic crystal optical resonator comprising:
a plate-like photonic crystal body including a base and a plurality of columnar lattice elements having a refractive index different from a refractive index of the base, the plurality of lattice elements being spaced apart on the base in a lattice shape at an interval equal to or less than a wavelength of target light;
a light confinement portion comprising a defect provided by a portion in which no lattice element is present at a lattice point of the photonic crystal body; and
an embedded structural body having a longitudinal direction which extends in a first direction along a Γ-K crystal orientation of a photonic crystal formed by the lattice elements, the embedded structural body being embedded in the base in the light confinement portion and having a refractive index less than the refractive index of the base;
wherein one of resonant modes of the resonator formed by the light confinement portion is in a state of having only one electric-field antinode in the embedded structural body;
wherein the embedded structural body has a refractive index greater than a refractive index of air;
wherein first lattice elements of the plurality of lattice elements adjacent to the light confinement portion in a second direction perpendicular to the first direction on a plane in which the plurality of lattice elements are arranged are configured to shift from first lattice points to separate from the light confinement portion in the second direction;
wherein second lattice elements of the plurality of lattice elements adjacent to the first lattice elements in the first direction are configured to shift from second lattice points to separate from the light confinement portion in the second direction;
wherein third lattice elements of the plurality of lattice elements adjacent to the first lattice elements and the second lattice elements on a side separating from the light confinement portion in the second direction are configured to shift from third lattice points to separate from the light confinement portion in the second direction;
wherein a shift amount of the first lattice elements is 0.05 to 0.5 times as large as a crystal period;
wherein a shift amount of the second lattice elements is 0.02 to 0.5 times as large as the crystal period; and
wherein a shift amount of the third lattice elements is 0.01 to 0.5 times as large as the crystal period.