Isolator and Magnetization Method of Isolator

Abstract

The isolator 10 has an optical chip 11, a first substrate 12, a first magnetic body portion 13, and a second magnetic body portion 14. The optical chip 11 includes a waveguide 16. The waveguide 16 propagates an electromagnetic wave along an extending direction. The optical chip 11 is mounted on the first substrate 12. The first magnetic body portion 13 is fixed to one side in a first direction with respect to the waveguide 16. The first direction is perpendicular to the extending direction and parallel to the main surface of the first substrate 12. The first magnetic body portion 13 includes at least one magnetic body. The second magnetic body portion 14 is fixed to the other side in the first direction with respect to the waveguide 16. The second magnetic body portion 14 includes at least one magnetic body.

Description

Technical Field

[0001] The present invention relates to an isolator and a magnetization method for an isolator.

Background Art

[0002] An isolator whose transmittance varies depending on the propagation direction of electromagnetic waves is known. In a waveguide type isolator, a magneto-optical effect is manifested by applying a magnetic field to a non-reciprocal member provided near the waveguide (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to exhibit non-reciprocity, it is necessary to apply a strong magnetic field. In order to apply a strong magnetic field, applying a magnetic field from outside the chip including the waveguide has been considered. However, applying a magnetic field from outside the chip makes the magnetic field in the chip non-uniform, resulting in non-uniformity of the magneto-optical effect.

[0005] Therefore, an object of the present disclosure made in view of the problems of the prior art as described above is to provide an isolator and a magnetization method for an isolator that reduce non-uniformity of the magneto-optical effect.

Means for Solving the Problems

[0006] In order to solve the above-described various problems, an isolator according to a first aspect includes a waveguide that propagates electromagnetic waves along an extending direction and a second substrate on which the waveguide is laminated an optical chip including the waveguide, a first substrate on which the optical chip is mounted, A first magnetic body part that is fixed to one side in a first direction perpendicular to the extending direction and parallel to the main surface of the first substrate with respect to the waveguide and includes at least one magnetic body, A second magnetic body part that is fixed to the other side in the first direction with respect to the waveguide and includes at least one magnetic body, a third substrate laminated adjacent to the optical chip, and is provided with 、 the first magnetic body portion and the second magnetic body portion are fixed to a recess formed in any one of the first substrate, the second substrate, and the third substrate, or a hole drilled from the optical chip so as to reach into the third substrate .

[0007] The magnetization method of the isolator according to the second aspect is An optical chip including a waveguide that propagates an electromagnetic wave along an extending direction and a second substrate on which the waveguide is laminated a first substrate on which the optical chip is mounted, a first magnetic body part that is fixed to one side in a first direction perpendicular to the extending direction and parallel to the main surface of the first substrate with respect to the waveguide and includes at least one magnetic body, and a second magnetic body part that is fixed to the other side in the first direction with respect to the waveguide and includes at least one magnetic body, a third substrate laminated adjacent to the optical chip, and is provided with the first magnetic body portion and the second magnetic body portion are fixed to a recess formed in any one of the first substrate, the second substrate, and the third substrate, or a hole drilled from the optical chip so as to reach into the third substrate The first magnetic body part and the second magnetic body part of the isolator are magnetized in the first direction

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

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Figure 5

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Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of an isolator to which the present disclosure is applied will be described with reference to the drawings.

[0010] As shown in FIG. 1, an isolator 10 according to the first embodiment includes an optical chip 11, a first substrate 12, a first magnetic body portion 13, and a second magnetic body portion 14. The isolator 10 may further include a third substrate 18.

[0011] The optical chip 11 may include a second substrate 15, a waveguide 16, and an insulating layer 17.

[0012] The second substrate 15 may be flat. The second substrate 15 may be formed of a material having a refractive index lower than that of the material forming the waveguide 16. The second substrate 15 is formed of, for example, Si or the like.

[0013] The waveguide 16 may be directly or indirectly laminated on the second substrate 15. The waveguide 16 may extend along the main surface of the second substrate 15. The main surface is the widest surface among the plurality of planes defining the second substrate 15. The waveguide 16 propagates an electromagnetic wave along the extending direction.

[0014] At least a part of the waveguide 16 may be at the same position as the first magnetic body portion 13 and the second magnetic body portion 14 in the normal direction of the main surface of the first substrate 12. In other words, the height position in the normal direction of at least a part of the waveguide 16 with respect to the first substrate 12 may be equal to the height positions of the first magnetic body portion 13 and the second magnetic body portion 14. Preferably, as shown in FIG. 2, in the normal direction, the center of the waveguide 16 may be located at the same height position as the centers of the first magnetic body portion 13 and the second magnetic body portion 14.

[0015] As described above, the waveguide 16 may be formed of a material having a refractive index higher than that of the material forming the second substrate 15. The waveguide 16 may be formed of, for example, Si, SiN, SiO x and the like.

[0016] The insulating layer 17 may be located on the main surface of the second substrate 15. The insulating layer 17 may be located around the waveguide 16. Specifically, the insulating layer 17 may be interposed between the second substrate 15 and the waveguide 16. Also, the insulating layer 17 may be located on both sides in the width direction of the waveguide 16. The width direction is a direction perpendicular to the extending direction and the normal direction of the waveguide 16.

[0017] The insulating layer 17 may be formed of a material having a refractive index lower than that of the material forming the waveguide 16. The insulating layer 17 may be formed of, for example, SiO 2 、SiO x 、SiON and the like.

[0018] The first substrate 12 may be flat. An optical chip 11 is mounted on the first substrate 12. On the first substrate 12, the main surface of the second substrate 15 in the optical chip 11 may be parallel to the main surface of the first substrate 12. On the first substrate 12, the optical chip 11 may be laminated via a third substrate 18. The first substrate 12 may be formed of an arbitrary material. For example, the first substrate 12 may be an organic substrate or a ceramic substrate. The third substrate 18 may be laminated adjacent to the optical chip 11 between the first substrate 12 and the optical chip 11. The third substrate 18 is an interposer layer, SiO 2 layer provided to meet desired requirements.

[0019] The first magnetic body portion 13 is fixed to one side in the first direction with respect to the waveguide 16. The first direction is perpendicular to the extending direction and parallel to the main surface of the first substrate 12. Therefore, the first direction is parallel to the width direction. The first magnetic body portion 13 includes at least one magnetic body. In the example shown in FIG. 1, the first magnetic body portion 13 is one magnetic body as a whole. Or, as shown in FIG. 3, the first magnetic body portion 13 may include a plurality of magnetic bodies 19. The plurality of magnetic bodies 19 may be arranged along the extending direction.

[0020] The second magnetic body portion 14 is fixed to the other side in the first direction with respect to the waveguide 16. The second magnetic body portion 14 includes at least one magnetic body. In the example shown in FIG. 1, the second magnetic body portion 14 is one magnetic body as a whole. Or, as shown in FIG. 3, the second magnetic body portion 14 may include a plurality of magnetic bodies 19. The plurality of magnetic bodies 19 may be arranged along the extending direction.

[0021] As shown in FIGS. 1 and 2, the magnetic body included in the first magnetic body portion 13 and the magnetic body included in the second magnetic body portion 14 may face each other with the waveguide 16 interposed therebetween. Or, as shown in FIG. 4, in a configuration in which each of the first magnetic body portion 13 and the second magnetic body portion 14 includes a plurality of magnetic bodies 19, the plurality of magnetic bodies 19 included in the first magnetic body portion 13 and the plurality of magnetic bodies 19 included in the second magnetic body portion 14 may be displaced in the extending direction.

[0022] The first magnetic body portion 13 and the second magnetic body portion 14 may be fixed to the waveguide 16 in various configurations. In the first embodiment, as shown in FIG. 1, the first magnetic body portion 13 and the second magnetic body portion 14 may be fixed to, for example, the recess 20 formed in the second substrate 15. For fixing to the recess 20, for example, an adhesive or a covering material may be used.

[0023] In the first embodiment, the magnetic bodies included in the first magnetic body portion 13 and the second magnetic body portion 14 may be spherical. In a configuration where the entire first magnetic body portion 13 and the second magnetic body portion 14 are magnetic bodies, the first magnetic body portion 13 and the second magnetic body portion 14 may be spherical. In a configuration where the first magnetic body portion 13 and the second magnetic body portion 14 are spherical, the recess 20 may be in the shape of a square pyramid or a rectangular parallelepiped. That the recess 20 is in the shape of a square pyramid means that the shape of the depression defined by the recess 20 is in the shape of a square pyramid. That the recess 20 is in the shape of a rectangular parallelepiped means that the shape of the depression defined by the recess 20 is in the shape of a rectangular parallelepiped.

[0024] As shown in FIGS. 5 and 6, in the first embodiment, the magnetic bodies included in the first magnetic body portion 13 and the second magnetic body portion 14 may be rod-shaped. In a configuration where the entire first magnetic body portion 13 and the second magnetic body portion 14 are magnetic bodies, the first magnetic body portion 13 and the second magnetic body portion 14 may be rod-shaped. In a configuration where the first magnetic body portion 13 and the second magnetic body portion 14 are rod-shaped, as shown in FIG. 5, the recess 20 may be in the shape of a groove extending in the extending direction. Alternatively, in a configuration where the first magnetic body portion 13 and the second magnetic body portion 14 are rod-shaped, as shown in FIG. 6, the recess 20 may be in the shape of a groove extending in a direction perpendicular to the extending direction (width direction). The groove-shaped recess 20 may have a V-shaped or rectangular cross-section.

[0025] The direction of the magnetic field by the first magnetic body portion 13 and the second magnetic body portion 14 may be substantially parallel to the first direction (width direction). The isolator 10 may not be magnetized before being provided to the installation target. The magnetization of the first magnetic body portion 13 and the second magnetic body portion 14 in the first direction (width direction) may be performed after the isolator 10 is provided to the installation target.

[0026] The isolator 10 may be generated by forming the recess 20 in the second substrate 15 by wet etching, applying an adhesive to the recess 20, dropping the first magnetic body portion 13 and the second magnetic body portion 14 into the recess 20, and solidifying the adhesive.

[0027] The isolator 10 of the first embodiment configured as described above includes an optical chip 11 including a waveguide 16 that propagates electromagnetic waves along an extending direction, a first substrate 12 on which the optical chip 11 is mounted, a first magnetic body portion 13 fixed in one direction of a first direction perpendicular to the extending direction with respect to the waveguide 16 and parallel to the main surface of the first substrate 12 and including at least one magnetic body, and a second magnetic body portion 14 fixed in the other direction of the first direction with respect to the waveguide 16 and including at least one magnetic body. With such a configuration, in the isolator 10, since the waveguide 16 is sandwiched between the first magnetic body portion 13 and the second magnetic body portion 14 in the first direction, the non-uniformity of the magneto-optical effect can be reduced. Also, in the isolator 10, since it is not necessary to apply a magnetic field from the outside of the isolator 10, the device using the isolator 10 can be miniaturized.

[0028] Also, in the isolator 10 of the first embodiment, in the normal direction of the main surface of the first substrate 12, at least a part of the waveguide 16 is located overlapping the first magnetic body portion 13 and the second magnetic body portion 14. With such a configuration, the isolator 10 can position the waveguide 16 in a region with a large magnetic flux density between the first magnetic body portion 13 and the second magnetic body portion 14. Therefore, the isolator 10 can apply a large magnetic field to the waveguide 16.

[0029] Also, in the first embodiment, in the isolator 10, the magnetic body included in the first magnetic body portion 13 and the magnetic body included in the second magnetic body portion 14 face each other with the waveguide 16 interposed therebetween. With such a configuration, the isolator 10 can maximize the magnetic field applied to the waveguide 16.

[0030] Further, in the isolator 10 of the first embodiment, a plurality of magnetic bodies 19 included in the first magnetic body portion 13 and arranged along the extending direction, and a plurality of magnetic bodies 19 included in the second magnetic body portion 14 and arranged along the extending direction are positioned with a shift in the extending direction while sandwiching the waveguide 16. With such a configuration, the isolator 10 can homogenize the magnetic flux density in the extending direction while applying a relatively large magnetic field to the waveguide 16 in a longer range along the extending direction. Therefore, the isolator 10 can facilitate the assumption of performance because simulation analysis is easy due to the homogenization of the magnetic flux density. Further, the isolator 10 can average the magnetic flux density even when manufacturing problems occur spotwise on the waveguide 16 due to the homogenization of the magnetic flux density.

[0031] Further, in the isolator 10 of the first embodiment, the first magnetic body portion 13 and the second magnetic body portion 14 are fixed to the recess 20 formed in the second substrate 15 on which the waveguide 16 is laminated in the optical chip 11. With such a configuration, the isolator 10 can dispose the first magnetic body portion 13 and the second magnetic body portion 14 on another substrate for fixing, or can eliminate the need for the substrate.

[0032] Further, in the isolator 10 of the first embodiment, the magnetic bodies included in the first magnetic body portion 13 and the second magnetic body portion 14 are spherical, and the recess 20 is in the shape of a square pyramid or a rectangular parallelepiped. With such a configuration, the isolator 10 can easily fix the magnetic bodies with high positional accuracy by rolling the magnetic bodies on the second substrate 15 during manufacturing and hooking them on the recess 20.

[0033] Further, in the isolator 10 of the first embodiment, the magnetic bodies included in the first magnetic body portion 13 and the second magnetic body portion 14 are rod-shaped, and the recess 20 is in the shape of a groove extending in the extending direction or a direction perpendicular to the extending direction. With such a configuration, the isolator 10 can easily fix the magnetic bodies with high positional accuracy by rolling the magnetic bodies on the second substrate 15 during manufacturing and hooking them on the recess 20.

[0034] Further, the magnetization method of the isolator 10 of the first embodiment magnetizes the first magnetic body portion 13 and the second magnetic body portion 14 of the isolator 10 in the first direction. The isolator 10 is assumed to be installed in various devices. It is assumed that elements other than the isolator 10 are installed in the device to be installed. Therefore, if the isolator 10 before installation in the device to be installed contains a magnetized magnetic body, a decrease in workability is predicted due to magnetic force when installing the isolator 10 and other elements in the installation target. For such an event, the magnetization method having the above-described configuration magnetizes the isolator 10 after it is installed in the installation target, so that the above-described decrease in workability can be reduced. Further, the installation of the pre-magnetized first magnetic body portion 13 and second magnetic body portion 14 on the second substrate 15 makes it difficult to improve the positional accuracy because they exert magnetic forces on each other. On the other hand, with the above-described configuration, the magnetization method can easily fix the first magnetic body portion 13 and the second magnetic body portion 14 at accurate positions.

[0035] Next, a second embodiment of the present disclosure will be described. In the second embodiment, the configuration for fixing the first magnetic body portion and the second magnetic body portion is different from that of the first embodiment. Hereinafter, the second embodiment will be described centering on the points different from the first embodiment. Note that the same reference numerals are given to the parts having the same configuration as those in the first embodiment.

[0036] As shown in FIG. 7, the isolator 100 according to the second embodiment includes an optical chip 11, a first substrate 12, a first magnetic body portion 130, and a second magnetic body portion 140. The structures and functions of the optical chip 11, the first substrate 12, and the third substrate 18 are the same as those in the first embodiment.

[0037] The first magnetic body portion 130 is fixed to one side in the first direction with respect to the waveguide 16, similarly to the first embodiment. The first magnetic body portion 130 includes at least one magnetic body, similarly to the first embodiment. The second magnetic body portion 140 is fixed to the other side in the first direction with respect to the waveguide 16, similarly to the first embodiment. The second magnetic body portion 14 includes at least one magnetic body, similarly to the first embodiment.

[0038] Unlike the first embodiment, the first magnetic body portion 130 and the second magnetic body portion 140 may be fixed to at least the third substrate 18. For example, as shown in FIG. 7, the first magnetic body portion 130 and the second magnetic body portion 140 may be fixed to a hole 210 drilled so as to reach into the third substrate 18 from the optical chip 11. Also, for example, as shown in FIG. 8, the first magnetic body portion 130 and the second magnetic body portion 140 may be fixed to a recess 220 formed in the third substrate 18. For fixing to the hole 210 or the recess 220, for example, an adhesive or a covering material may be used.

[0039] The isolator 100 of the second embodiment configured as described above also includes an optical chip 11 including a waveguide 16 that propagates an electromagnetic wave along an extending direction, a first substrate 12 on which the optical chip 11 is mounted, a first magnetic body portion 130 that is fixed in one direction of a first direction perpendicular to the extending direction with respect to the waveguide 16 and parallel to a main surface of the first substrate 12 and includes at least one magnetic body, and a second magnetic body portion 140 that is fixed in the other direction of the first direction with respect to the waveguide 16 and includes at least one magnetic body. Therefore, the isolator 100 can also reduce the non-uniformity of the magneto-optical effect. Also, the isolator 100 can also miniaturize a device using the isolator 100.

[0040] Also, in the isolator 100 of the second embodiment, at least a part of the waveguide 16 overlaps with the first magnetic body portion 130 and the second magnetic body portion 140 in a normal direction of the main surface of the first substrate 12. Therefore, the isolator 100 can also apply a large magnetic field to the waveguide 16.

[0041] Also, in the second embodiment, in the isolator 100, the magnetic body included in the first magnetic body portion 130 and the magnetic body included in the second magnetic body portion 140 face each other with the waveguide 16 interposed therebetween. Therefore, the isolator 100 can also maximize the magnetic field applied to the waveguide 16.

[0042] Also, in the isolator 100 of the second embodiment, the plurality of magnetic bodies 19 included in the first magnetic body portion 130 and arranged along the extending direction, and the plurality of magnetic bodies 19 included in the second magnetic body portion 140 and arranged along the extending direction are positioned shifted in the extending direction while sandwiching the waveguide 16. Therefore, the isolator 100 can also homogenize the magnetic flux density in the extending direction while applying a relatively large magnetic field to the waveguide 16 in a longer range along the extending direction. Therefore, the isolator 100 can also facilitate the assumption of performance because simulation analysis is easy due to the homogenization of the magnetic flux density. Also, the isolator 10 can also average the magnetic flux density even when spot-like manufacturing problems occur on the waveguide 16 due to the homogenization of the magnetic flux density.

[0043] Also, in the isolator 100 of the second embodiment, the first magnetic body portion 130 and the second magnetic body portion 140 are fixed to a hole 210 drilled from the optical chip 11 so as to reach into a third substrate 18 laminated adjacent to the optical chip 11. With such a configuration, the isolator 100 can use the first magnetic body portion 130 and the second magnetic body portion 140 having a large volume. Therefore, the isolator 100 can magnetize the first magnetic body portion 130 and the second magnetic body portion 140 with a large magnetic force.

[0044] Also, in the isolator 100 of the second embodiment, the first magnetic body portion 130 and the second magnetic body portion 140 are fixed to a recess 220 formed in a third substrate 18 laminated adjacent to the optical chip 11. With such a configuration, the isolator 100 can use the first magnetic body portion 130 and the second magnetic body portion 140 having a large volume. Therefore, the isolator 100 can magnetize the first magnetic body portion 130 and the second magnetic body portion 140 with a large magnetic force.

[0045] The drawings for explaining the embodiments according to the present disclosure are schematic. The dimensional ratios and the like on the drawings do not necessarily match the actual ones.

[0046] Embodiments according to the present disclosure have been described based on the drawings and examples. It should be noted that those skilled in the art can easily make various modifications or corrections based on the present disclosure. Therefore, it should be noted that these modifications or corrections are included in the scope of the present disclosure. For example, functions included in each component or each step, etc. can be rearranged so as not to be logically contradictory, and a plurality of components or steps, etc. can be combined into one or divided.

[0047] For example, in the second embodiment, the third substrate 18 is configured to be laminated between the first substrate 12 and the optical chip 11, but it only needs to be adjacent to the optical chip 11. For example, as shown in FIG. 9, the third substrate 18 is located adjacent to the optical chip 11 on the side opposite to the first substrate 12, and the first magnetic body portion 130 and the second magnetic body portion 140 may be fixed to the hole 210 formed so as to reach from the optical chip 11 into the third substrate 18.

[0048] Also, for example, in the second embodiment, the first magnetic body portion 130 and the second magnetic body portion 140 are configured to be fixed to the recess 220 formed in the third substrate 18, but they may be fixed to the recess formed in the first substrate 12.

[0049] In the present disclosure, descriptions such as "first" and "second" are identifiers for distinguishing the configurations. The configurations distinguished by the descriptions such as "first" and "second" in the present disclosure can have their numbers in the configuration exchanged. For example, the first mask layer can have the identifiers "first" and "second" exchanged with the second mask layer. The exchange of identifiers is performed simultaneously. The configurations are still distinguishable after the exchange of identifiers. The identifiers may be deleted. The configurations with the identifiers deleted are distinguished by reference numerals. Based only on the descriptions of the identifiers such as "first" and "second" in the present disclosure, the order of the configurations should not be interpreted, nor should it be used as the basis for the existence of identifiers with smaller numbers.

Description of Reference Numerals

[0050] 10, 100 Isolator 11 Optical Chip 12 Substrate 13, 130 First magnetic body part 14, 140 Second magnetic body part 15 Second substrate 16 Waveguide 17 Insulating layer 18 Third substrate 19 Magnetic body 20 Concavity 210 Hole 220 Concavity

Claims

1. An optical chip including a waveguide that propagates an electromagnetic wave along an extending direction, and a second substrate on which the waveguide is laminated, a first substrate on which the optical chip is mounted, a first magnetic body portion that is fixed to one of a first direction perpendicular to the extending direction and parallel to the main surface of the first substrate with respect to the waveguide and includes at least one magnetic body, a second magnetic body portion that is fixed to the other of the first direction with respect to the waveguide and includes at least one magnetic body, a third substrate that is laminated adjacent to the optical chip, and the first magnetic body portion and the second magnetic body portion are fixed to a recess formed in any one of the first substrate, the second substrate, and the third substrate, or a hole drilled from the optical chip so as to reach the inside of the third substrate Isolator.

2. In the isolator according to Claim 1, in a normal direction of the main surface of the first substrate, at least a part of the waveguide is at the same position as the first magnetic body portion and the second magnetic body portion Isolator.

3. In the isolator according to Claim 1 or 2, the magnetic body included in the first magnetic body portion and the magnetic body included in the second magnetic body portion face each other with the waveguide interposed therebetween Isolator.

4. In the isolator according to Claim 1 or 2, a plurality of magnetic bodies included in the first magnetic body portion and arranged along the extending direction, and a plurality of magnetic bodies included in the second magnetic body portion and arranged along the extending direction are shifted in the extending direction while sandwiching the waveguide Isolator.

5. In the isolator according to Claim 1 or 2, the magnetic bodies included in the first magnetic body portion and the second magnetic body portion are spherical, the first magnetic body portion and the second magnetic body portion are fixed to the quadrangular pyramid-shaped or rectangular parallelepiped-shaped recess formed in the second substrate Isolator.

6. In the isolator according to Claim 1 or 2, the magnetic bodies included in the first magnetic body portion and the second magnetic body portion are rod-shaped, the first magnetic body portion and the second magnetic body portion are fixed to the groove-shaped recess formed in the second substrate in the extending direction or a direction perpendicular to the extending direction Isolator.

7. Magnetizing the first magnetic body portion and the second magnetic body portion of the isolator according to Claim 1 or 2 in the first direction Magnetization method of isolator.

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