Photon detector
Provided is a photon detector. The photon detector includes an optical waveguide including input and detection regions, which are spaced apart from each other in a first direction, and a conversion region between the input region and the detection region, a nano pattern disposed on the optical waveguide in the conversion region, and a nanowire disposed on the optical waveguide in the detection region. The nano pattern includes a first pattern and a second pattern, which extend in the first direction, and the first pattern and the second pattern are spaced apart from each other in a second direction crossing the first direction.
1. A photon detector comprising:
an optical waveguide comprising input and detection regions, which are spaced apart from each other in a first direction, and a conversion region between the input region and the detection region;
a nano pattern disposed on the optical waveguide in the conversion region; and
a nanowire disposed on the optical waveguide in the detection region,
wherein the nano pattern comprises a first pattern and a second pattern, which extend in the first direction,
the first pattern and the second pattern are spaced apart from each other in a second direction crossing the first direction,
a distance between the first pattern and the second pattern is less than a width, in the second direction, of each of the first pattern and the second pattern,
the nanowire comprises first portions, which extend in the first direction and are spaced apart from each other, and a second portion connecting the first portions to each other, and
the first portions are at least partially covered by the first pattern and the second pattern in a plan view, and
the second portion extends between the first pattern and the second pattern in the plan view such that the second portion is at least partially exposed in a space between the first pattern and the second pattern.
2. The photon detector of claim 1 , wherein the nano pattern has one side adjacent to the detection region and the other side facing the one side, and
each of the first pattern and the second pattern has a uniform width from the one side to the other side.
3. The photon detector of claim 1 , wherein the first pattern and the second pattern are disposed in parallel to each other.
4. The photon detector of claim 1 , wherein the nano pattern comprises a metal and is optically coupled to the optical waveguide.
5. The photon detector of claim 4 , wherein the conversion region is configured to convert light inputted into the input region of the optical waveguide into surface plasmon-polaritons.
6. The photon detector of claim 1 , further comprising a buffer layer between the optical waveguide and the nano pattern,
wherein the buffer layer comprises a material having a refractive index less than that of the optical waveguide.
7. The photon detector of claim 6 , wherein the buffer layer directly contacts the optical waveguide and the nano pattern.
8. The photon detector of claim 1 , wherein the nanowire comprises a superconducting material.
9. The photon detector of claim 1 , further comprising metal pads that cover both ends of the nanowire, respectively.
10. The photon detector of claim 1 , wherein
the second portion is disposed adjacent to an end of the nano pattern.
11. The photon detector of claim 10 , wherein the first portion of the nanowire extends in the second direction.
12. The photon detector of claim 1 , wherein the optical waveguide comprises a first protrusion protruding from one surface of the optical waveguide and a second protrusion protruding from the other surface facing the one surface, and
the nanowire extends from a top surface of the first protrusion to a top surface of the second protrusion.
13. The photon detector of claim 12 , wherein the nanowire has a straight line shape.
14. The photon detector of claim 12 , wherein the optical waveguide further comprises an extension region, and
the extension region extends from the detection region in a direction that is away from the conversion region.
15. The photon detector of claim 1 , wherein at least a portion of the nanowire is disposed between the optical waveguide and the nano pattern.
16. The photon detector of claim 15 , wherein the nanowire comprises first portions, which extend in the first direction and are spaced apart from each other, and a second portion connecting the first portions to each other, and
at least a portion of the second portion is disposed between the first pattern and the second pattern.
17. The photon detector of claim 1 , further comprising a buffer layer on the waveguide and extending contiguously on the waveguide over the input region, over the conversion region, and over the detection region, the buffer layer located between the waveguide and the nano pattern and between the waveguide and the nanowire, and
wherein the buffer layer has a refractive index less than a refractive index of the waveguide.
18. The photon detector of claim 1 , the first pattern and the second pattern each have a width less than 50 nm.
19. The photon detector of claim 1 , wherein a surface of the waveguide on which the nano pattern is disposed is flat and co-planar with a surface of the waveguide on which the nanowire is disposed.