Three-dimensional photonic crystal and its manufacturing method thereof
An object of the present invention is to provide a three-dimensional photonic crystal which allows an internal formation of a defect structure with an arbitrary shape and size. Multiple holes extending to two different directions are formed obliquely to a base body surface in order to form a first crystal and a second crystal. Base body left between the holes are made to be rods. Moreover, a connection crystal layer is formed by a part of rods having a size different from that of the rods in the first crystal and the second crystal. The connection crystal layer is held between the first crystal and the second crystal and they are fused. In a three-dimensional photonic crystal thus obtained, the rod becomes a point defect. The shape and size of the point defect can be arbitrarily set in any directions within the connection crystal layer. The shape and size of the point defect can also be controlled by adjusting the thickness of the connection crystal layer.
1. A three-dimensional photonic crystal, comprising:
a) a first three-dimensional photonic crystal and a second three-dimensional photonic crystal, in which a dielectric base body of each of the first three-dimensional photonic crystal and the second three-dimensional photonic crystal contains multiple holes fabricated obliquely to a surface of the base body from two different directions so as to form a two-dimensional cyclic pattern; and
b) a connection crystal layer inserted between the first three-dimensional photonic crystal and the second three-dimensional photonic crystal, the connection crystal layer being a photonic crystal layer of a dielectric substance having a predetermined thickness, which partially mismatches the first three-dimensional photonic crystal and the second three-dimensional photonic crystal and matches the first three-dimensional photonic crystal and the second three-dimensional photonic crystal in the remaining portion.
2. The three-dimensional photonic crystal according to claim 1 , wherein the connection crystal layer has the same crystal structure with the first three-dimensional photonic crystal and the second three-dimensional photonic crystal in the matching portion.
3. The three-dimensional photonic crystal according to claim 1 , wherein the connection crystal layer has a two-dimensional structure.
4. The three-dimensional photonic crystal according to claim 1 , wherein a stripe pattern made by alternately existing base body portions and hole portions is formed in joint planes of the first three-dimensional photonic crystal and the second three-dimensional photonic crystal to the connection crystal layer.
5. The three-dimensional photonic crystal according to claim 1 , wherein the mismatching portions are linearly connected in a direction parallel to the connection crystal layer.
6. The three-dimensional photonic crystal according to claim 1 , wherein the connection crystal layer is made of a light emitting material and provided with electrodes to inject currents to the light emitting material on both surfaces thereof.
7. The three-dimensional photonic crystal according to claim 1 , wherein the holes extending from the vicinity of the mismatching portion of the connection crystal layer to the outside are partially different from the remaining holes in the first three-dimensional photonic crystal and the second three-dimensional photonic crystal.
8. The three-dimensional photonic crystal according to claim 1 , wherein connection crystal layers are inserted between adjacent layers of three or more layers of main body crystal similar to the first three-dimensional photonic crystal and the second three-dimensional photonic crystal.
9. The three-dimensional photonic crystal according to claim 8 , wherein holes to connect the mismatching portions of the two connection crystal layers in the main body crystal between the two connection crystal layers are different form the remaining holes.
10. The three-dimensional photonic crystal according to claim 1 , wherein the first three-dimensional photonic crystal and the second three-dimensional photonic crystal are formed with:
multiple holes extending to a first direction in a cycle a 1 from a 4n-th (n is an integer) region out of a plurality of band regions obtained by dividing the surface of the base body;
multiple holes extending in a cycle a 2 from a (4n+1)-th region to a second direction being different from the first direction;
multiple holes extending in the cycle a 1 from a (4n+2)-th region to the first direction in a position deviated from the holes of the 4n-th region by a 1 /2 in a longitudinal direction of the bands; and
multiple holes extending in the cycle a 2 from a (4n+3)-th region to the second direction in a position deviated from the holes of the (4n+1)-th region by a 2 /2 in the longitudinal direction of the bands.
11. The three-dimensional photonic crystal according to claim 10 , wherein the base body with the perforated holes has a stacked rod shape and the first direction is substantially orthogonal to the second direction.