Non-reversible circuit element

Abstract

The irreversible circuit element includes a metal layer, a loss layer, and a magnet. The metal layer includes a first terminal, a second terminal, and a third terminal. The loss layer includes a magnetic body and an absorber. The magnetic body overlaps a first region of the metal layer in a thickness direction. The absorber overlaps a second region of the metal layer in the thickness direction. The magnet and the metal layer at least sandwich the magnetic body in the thickness direction. When viewed from the thickness direction, the shortest width of a first side of the metal layer connecting the first terminal and the second terminal and a second side of the absorber on the side of the first terminal and the second terminal is smaller than the shortest width of the first side of the metal layer connecting the first terminal and the second terminal. The width is shorter than the width between a first straight line connecting both ends of the first side and a second straight line connecting both ends of the second side.

Description

Technical Field

[0001] The present invention relates to a non-reciprocal circuit element. Background Art

[0002] A non-reciprocal circuit element is an element that specifies the transmission direction of a high-frequency signal. An isolator and a circulator are examples of non-reciprocal circuit elements. Non-reciprocal circuit elements are widely used in circuits that transmit high-frequency signals.

[0003] Non-reciprocal circuit elements are used in various places where high-frequency signals are used. For example, Patent Document 1 discloses an isolator for microwave communication. Also, Patent Document 2 discloses the use of an isolator in a quantum computer.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 4-287403

[0007] Patent Document 1: Japanese Patent No. 6998459 Summary of the invention

[0008] The technical problem that the invention is intended to solve

[0009] If the frequency of the input signal becomes higher, there is a problem that the isolation characteristics of the isolator are degraded.

[0010] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a non-reciprocal circuit element whose isolation characteristics are unlikely to be degraded even when a high-frequency input signal is input.

[0011] Means for solving technical problems

[0012] In order to solve the above-mentioned technical problems, the present invention provides the following means.

[0013] (1) The non-reciprocal circuit element of this embodiment comprises a metal layer, a loss layer and a magnet. The metal layer comprises a first terminal, a second terminal and a third terminal. The loss layer comprises a magnetic body and an absorber. The magnetic body overlaps with a first region of the metal layer in the thickness direction. The absorber overlaps with a second region of the metal layer in the thickness direction. The first region extends over the first terminal and the second terminal. The second region extends between the first terminal and the third terminal, and between the second terminal and the third terminal. The magnet and the metal layer at least clamp the magnetic body in the thickness direction. When viewed from the thickness direction, the side of the metal layer connecting the first terminal and the second terminal is set as the first side, and the side of the absorber on the first terminal and the second terminal side is set as the second side, then the shortest width of the first side and the second side is shorter than the width between the first straight line connecting the two ends of the first side and the second straight line connecting the two ends of the second side.

[0014] (2) In the non-reciprocal circuit element of the above aspect, the widths of the first side and the second side may be shortest at a midpoint of the first side.

[0015] (3) In the non-reciprocal circuit element according to the above aspect, the first side may be bent or curved toward the second straight line.

[0016] (4) In the non-reciprocal circuit element of the above aspect, the second side may be bent or curved toward the first straight line.

[0017] (5) In the non-reciprocal circuit element of the above aspect, the first side may be bent or curved toward the second straight line, and the second side may be bent or curved toward the first straight line.

[0018] (6) In the non-reciprocal circuit element of the above-mentioned embodiment, the shortest width may also satisfy the following formula (1). In formula (1), W1 is the shortest width, f0 is the maximum frequency of the input signal input to the first terminal or the second terminal, ε0 is the dielectric constant of vacuum, μ0 is the magnetic permeability of vacuum, ε eff is the effective dielectric constant of the magnetic body at frequency f0, μ eff It is the effective magnetic permeability of the magnetic body at the frequency f0 when a DC magnetic field is applied from the magnet to the magnetic body.

[0019]

[0020] (7) In the non-reciprocal circuit element of the above aspect, the third terminal may be grounded via a resistor or directly grounded.

[0021] Effects of the Invention

[0022] The non-reciprocal circuit element of the present invention is unlikely to have its isolation characteristics degraded even when a high-frequency input signal is input. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the non-reciprocal circuit element according to the first embodiment.

[0024] Figure 2 It is a plan view of a metal layer and a lossy layer of the non-reciprocal circuit element according to the first embodiment.

[0025] Figure 3 It is a top view of the metal layer of the non-reciprocal circuit board according to the first embodiment.

[0026] Figure 4 It is a top view of the lossy layer of the non-reciprocal wiring board according to the first embodiment.

[0027] Figure 5 It is a top view of the conductor and the magnet of the non-reciprocal circuit board according to the first embodiment.

[0028] Figure 6 It is a plan view of a metal layer and a lossy layer of the non-reciprocal circuit element according to the first modification.

[0029] Figure 7 It is a plan view of a metal layer and a lossy layer of a non-reciprocal circuit element according to a second modification.

[0030] Figure 8 It is a plan view of a metal layer and a lossy layer of a non-reciprocal circuit element according to a third modification.

[0031] Fig. 9 is a cross-sectional view of a non-reciprocal circuit element according to a fourth modification.

[0032] Fig.10 It is a cross-sectional view of the non-reciprocal circuit element according to the second embodiment.

[0033] Fig.11 It is a plan view of a metal layer and a lossy layer of the non-reciprocal circuit element according to the second embodiment.

[0034] Fig.12 It is a top view of the metal layer of the non-reciprocal circuit board according to the second embodiment.

[0035] Fig.13 It is a top view of the lossy layer of the non-reciprocal wiring board according to the second embodiment.

[0036] Fig.14 It is a top view of a metal layer and a lossy layer of a non-reciprocal circuit element according to a fifth modification.

[0037] Fig.15 It is a top view of a metal layer and a lossy layer of a non-reciprocal circuit element according to a sixth modification.

[0038] Fig.16 It is a top view of a metal layer and a lossy layer of a non-reciprocal circuit element according to a seventh variation.

[0039] Fig.17 It is a cross-sectional view of the non-reciprocal circuit element according to the third embodiment.

[0040] Fig.18 It is a plan view of a metal layer and a lossy layer of the non-reciprocal circuit element according to the third embodiment.

[0041] Fig.19 The following are the measurement results of the isolation characteristics of the non-reciprocal circuit elements of Example 1, Example 2, and Comparative Example 1.

[0042] Explanation of symbols

[0043] 10, 10A, 10B, 10C...metal layer; 11, 61...first region; 12, 62...second region; 21, 71...first loss layer; 22, 72...second loss layer; 25, 75...first magnetic body; 26, 76...first absorber; 27, 77...second magnetic body; 28, 78...second absorber; 31...first magnet; 32...second magnet; 41...first conductor; 42...second conductor; 50...resistor; 60... …metal layer; 100, 101, 101A, 101B, 101C, 101D, 102, 102A, 102B, 102C, 103…non-reversible circuit element; L1, L1'…first straight line; L2, L2'…second straight line; P1, P1'…midpoint; S1, S1'…first side; S2, S2'…second side; T1…first terminal; T2…second terminal; T3…third terminal; W1…shortest width; W2…width. DETAILED DESCRIPTION

[0044] Hereinafter, the present embodiment will be described in detail with reference to the drawings as appropriate. In the drawings used in the following description, in order to facilitate the understanding of the features, the features are sometimes enlarged for convenience, and the size ratios of the components are sometimes different from the actual ones. The materials, dimensions, etc. illustrated in the following description are examples, and the present invention is not limited thereto, and can be appropriately changed and implemented within the scope of achieving the effects of the present invention.

[0045] First, define the direction. Set one direction of the surface where the metal layer extends as the x direction. For example, set the direction of the metal layer connecting the first terminal and the second terminal as the x direction. In addition, on the surface where the metal layer extends, set the direction perpendicular to the x direction as the y direction. Set the direction perpendicular to the x direction and the y direction as the z direction. The thickness direction of each layer is an example of the z direction.

[0046] "First Implementation Method"

[0047] Figure 1 1 is a cross-sectional view of the non-reciprocal circuit element 101 according to the first embodiment. The non-reciprocal circuit element 101 includes, for example, a metal layer 10, a first loss layer 21, a second loss layer 22, a first magnet 31, a second magnet 32, a first conductor 41, and a second conductor 42. The non-reciprocal circuit element 101 functions as, for example, an isolator.

[0048] Figure 2 1 is a plan view of the metal layer 10 and the first lossy layer 21 of the non-reciprocal circuit element 101 according to the first embodiment. Figure 1 It is along Figure 2 The cross section cut along line AA. Figure 3 1 is a plan view of the metal layer 10 of the non-reciprocal circuit element 101 according to the first embodiment. Figure 4 1 is a plan view of the first loss layer 21 of the non-reciprocal circuit element 101 according to the first embodiment.

[0049] The metal layer 10 has a first terminal T1, a second terminal T2 and a third terminal T3. The first terminal T1, the second terminal T2 and the third terminal T3 correspond to the vertices of a triangle, for example. The first terminal T1 and the second terminal T2 are connected to external terminals. The third terminal T3 is, for example, an open end.

[0050] The metal layer 10 transmits high-frequency signals. The metal layer 10 transmits high-frequency signals irreversibly between the first terminal T1 and the second terminal T2. "Irreversibly transmitting high-frequency signals" means that the propagation efficiency of the signal varies depending on the direction. For example, the case where a signal is propagated with low loss in the forward direction but hardly propagated in the reverse direction qualifies as "irreversibly transmitting high-frequency signals". The propagation direction of the high-frequency signal in the metal layer 10 is controlled by the first loss layer 21 and the second loss layer 22 described later.

[0051] The high-frequency signal input from the first terminal T1 is transmitted to the second terminal T2 with low loss. The high-frequency signal input from the second terminal T2 is transmitted to the third terminal T3 with low loss. The high-frequency signal input from the third terminal T3 is transmitted to the first terminal T1 with low loss. The high-frequency signal input from the second terminal T2 reaches the first terminal T1 via the third terminal T3 and is mostly absorbed. That is, the high-frequency signal is hardly transmitted from the second terminal T2 to the first terminal T1. That is, the high-frequency signal is transmitted from the first terminal T1 toward the second terminal T2 with low loss, but is hardly transmitted from the second terminal T2 to the first terminal T1.

[0052] The metal layer 10 is not particularly limited as long as it transmits high-frequency signals with high efficiency. The metal layer 10 is, for example, aluminum, copper, silver, gold, stainless steel, etc. The metal layer 10 may also be a layer obtained by plating aluminum, copper, silver, gold, stainless steel, etc. on a non-conductor or a conductor with a high resistance value (such as phosphor bronze).

[0053] The metal layer 10 has a first region 11 and a second region 12. The first region 11 extends over the first terminal T1 and the second terminal T2. The first region 11 overlaps with the first magnetic body 25 in the z direction. The second region 12 extends between the first terminal T1 and the third terminal T3, and between the second terminal T2 and the third terminal T3. The second region 12 overlaps with the first absorber 26 in the z direction. When viewed from above in the z direction, a boundary between the first region 11 and the second region 12 exists between the first terminal T1 and the third terminal T3, and between the second terminal T2 and the third terminal T3.

[0054] The first side S1 of the metal layer 10 connecting the first terminal T1 and the second terminal T2 is bent. The first side S1 is bent toward the third terminal T3 side than the first straight line L1. The first side S1 is bent toward the second straight line L2. The first straight line L1 is a straight line connecting the first end S1A and the second end S1B of the first side S1. The second straight line L2 is a straight line connecting the first end S2A and the second end S2B of the second side S2 described later.

[0055] The first loss layer 21 and the second loss layer 22 sandwich the metal layer 10 in the z direction. The first loss layer 21 includes a first magnetic body 25 and a first absorber 26. The second loss layer 22 includes a second magnetic body 27 and a second absorber 28. The first loss layer 21 and the second loss layer 22 have substantially the same shape. The first loss layer 21 is located between the metal layer 10 and the first magnet 31. The second loss layer 22 is located between the metal layer 10 and the second magnet 32.

[0056] The first magnetic body 25 and the first absorber 26 are located at different positions in the xy plane. The second magnetic body 27 and the second absorber 28 are located at different positions in the xy plane. The first magnetic body 25 and the second magnetic body 27 are located at positions overlapping the first region 11 of the metal layer 10 in the z direction. The first absorber 26 and the second absorber 28 are located at positions overlapping the second region 12 of the metal layer 10 in the z direction.

[0057] The shapes of the first magnetic body 25 and the second magnetic body 27 are not limited as long as they can cover the first region 11 . The shapes of the first absorbent body 26 and the second absorbent body 28 are not limited as long as they can cover the second region 12 .

[0058] By applying a DC magnetic field to the first magnetic body 25 and the second magnetic body 27 using the first magnet 31 and the second magnet 32, the high-frequency signal passing through the metal layer 10 is propagated in a biased manner to one side of the traveling direction. For example, the high-frequency signal input from the first terminal T1 is propagated in a biased manner to the side of the metal layer 10 opposite to the third terminal T3, and propagates to the second terminal T2 with low loss. On the other hand, the high-frequency signal input to the second terminal T2 is propagated in a biased manner to the third terminal T3 side of the metal layer 10, and propagates to the first terminal T1. At this time, the high-frequency signal input to the second terminal T2 is greatly attenuated because it is absorbed by the first absorber 26 and the second absorber 28.

[0059] The first magnetic body 25 and the second magnetic body 27 include magnetic materials. The first magnetic body 25 and the second magnetic body 27 may be a conductor or an insulator. The first magnetic body 25 and the second magnetic body 27 are, for example, soft magnetic bodies. The first magnetic body 25 and the second magnetic body 27 include, for example, a material selected from Co-based amorphous, ferrite, Fe 85 Si2B8P4Cu、Fe 86 AlB8P4Cu、Fe 78 SiC 13 , yttrium iron garnet (YIG). YIG is, for example, Y3Fe2(FeO4)3, Y3Fe5O 12 .

[0060] The first magnetic body 25 and the second magnetic body 27 may also be magnetic bodies formed by mixing magnetic particles with resin. The magnetic particles include, for example, iron, silicon steel (Fe-Si), permalloy (Ni-Fe), permendur alloy (Fe-Co), iron silicon aluminum alloy (Fe-Si-Al), electromagnetic stainless steel, amorphous iron-based alloy (Fe-BC series, Fe-Co series), manganese zinc ferrite, nickel zinc ferrite, etc. The first magnetic body 25 and the second magnetic body 27 may also be magnetic bodies formed by mixing ferrite particles with resin.

[0061] When dispersing the magnetic material into an insulating material (such as resin, rubber, paint, etc.), the volume ratio of the magnetic material is preferably set to 10% or more and 70% or less. If the volume ratio of the magnetic material is small, the electromagnetic wave absorption capacity becomes small. If the volume ratio of the magnetic material is large, it becomes difficult to disperse into the insulating material.

[0062] The first absorber 26 and the second absorber 28 are made of a material having a greater magnetic field loss rate than the first magnetic body 25 and the second magnetic body 27. The first absorber 26 and the second absorber 28 are made of, for example, any one selected from iron, BN, conductive carbon, SiC, and Ni-based ferrite.

[0063] The second side S2 of the first absorber 26 is a straight line. The second side S2 is a side on the first terminal T1 and second terminal T2 sides of the first absorber 26. The second side S2 intersects a line that passes through the third terminal T3 and extends in the y direction.

[0064] The widths of the first side S1 and the second side S2 are, for example, the shortest width W1 at the midpoint P1 of the first side S1. The midpoint P1 is the center of the first side S1 in the x direction. Here, an example is shown in which the shortest width W1 is at the midpoint P1, but the shortest width W1 may also be at a position other than the midpoint P1.

[0065] The shortest width W1 is shorter than the width W2 between the first straight line L1 and the second straight line L2. As will be described in detail later, if the shortest width W1 is shorter than the width W2, the cutoff frequency moves to the high frequency side, and the isolation characteristic is not easily degraded even when a high frequency input signal is input.

[0066] The shortest width W1 preferably satisfies, for example, the following formula (1).

[0067]

[0068] Here, in formula (1), f0 is the maximum frequency of the input signal input to the first terminal T1 or the second terminal T2, ε0 is the dielectric constant of vacuum, μ0 is the magnetic permeability of vacuum, ε eff is the effective dielectric constant of the first magnetic body 25 at frequency f0, μ eff It is the effective magnetic permeability of the first magnetic body 25 at the frequency f0 when a DC magnetic field is applied from the first magnet 31 to the first magnetic body 25 .

[0069] Here, the shortest width W1 between the second side S2 of the first absorbent body 26 and the first side S1 of the metal layer 10 is described in detail, but the same relationship is preferably satisfied between the second side of the second absorbent body 28 and the first side S1 of the metal layer 10. That is, the shortest width between the second side of the second absorbent body 28 and the first side S1 of the metal layer 10 is preferably shorter than the width W2 between the first straight line L1 and the second straight line L2.

[0070] When the first lossy layer 21 and the second lossy layer 22 are conductors, an insulating layer is provided between the first lossy layer 21 and the metal layer 10 and between the second lossy layer 22 and the metal layer 10. As the insulating layer, a known insulating layer can be used.

[0071] The first magnet 31 and the second magnet 32 ​​sandwich the metal layer 10, the first loss layer 21, and the second loss layer 22 in the z direction. The first magnet 31 and the metal layer 10 sandwich the first loss layer 21 in the z direction. The second magnet 32 ​​and the metal layer 10 sandwich the second loss layer 22 in the z direction. The first magnet 31 and the second magnet 32 ​​apply a DC magnetic field to the metal layer 10.

[0072] Figure 5 1 is a top view of the first magnet 31 and the first conductor 41 of the non-reciprocal circuit element 101 of the first embodiment. The first magnet 31 and the second magnet 32 ​​are located at positions overlapping the first magnetic body 25 and the second magnetic body 27 when viewed from the z direction. The first magnet 31 and the second magnet 32 ​​may also overlap the first absorber 26 and the second absorber 28 when viewed from the z direction.

[0073] The first magnet 31 and the second magnet 32 ​​are, for example, hard magnetic bodies. The first magnet 31 and the second magnet 32 ​​may be insulators or conductors. The first magnet 31 and the second magnet 32 ​​include, for example, any one selected from ferrite magnets having insulation, rare earth magnets having conductivity, TbFeCo, GdFeCo, SmFeCo, [Co / Pt] multilayer films, and [Co / Pd] multilayer films. When the first magnet 31 and the second magnet 32 ​​are conductors, the first conductor 41 and the second conductor 42 may not be present.

[0074] The first conductor 41 is sandwiched between the first magnet 31 and the first loss layer 21. The second conductor 42 is sandwiched between the second magnet 32 ​​and the second loss layer 22. The first conductor 41 or the second conductor 42 is grounded to a reference potential, for example. The reference potential is, for example, a ground line. The first conductor 41 and the second conductor 42 are not particularly limited as long as they have conductivity.

[0075] Since the non-reciprocal circuit element 101 of this embodiment has a shortest width W1 that is shorter than the width W2, the isolation characteristics are not easily reduced even when a high-frequency input signal is input. In an edge-guided mode isolator, the high-frequency signal of the lowest-order mode is concentrated and propagated toward the end of the metal layer 10, but the high-frequency signals of higher-order modes are also distributed in the portion other than the end of the metal layer 10. Therefore, the high-frequency signal of the higher-order mode is not easily absorbed compared with the high-frequency signal of the lowest-order mode. If the width of the metal layer 10 in the direction orthogonal to the propagation direction of the high-frequency signal in the xy plane becomes the same as the half-wavelength of the electromagnetic wave, a high-frequency signal of a higher-order mode is generated. Therefore, by adjusting the shortest width W1, the cutoff frequency of the high-frequency signal of the higher-order mode can be increased, and the reduction in isolation characteristics caused by the high-frequency signal of the higher-order mode can be suppressed.

[0076] Although an example of the first embodiment has been described above, the present invention is not limited to these embodiments, and various modifications are possible.

[0077] Figure 6 1 is a top view of the non-reciprocal circuit element 101A of the first modification. The non-reciprocal circuit element 101A of the first modification is different from the non-reciprocal circuit element 101 in the top view shape of the metal layer 10 in the z direction. Figure 6 In the figure, the same components as those of the non-reciprocal circuit element 101 are denoted by the same reference numerals and their description is omitted.

[0078] In the metal layer 10A, the first side S1 is bent toward the third terminal T3 side relative to the first straight line L1. The first side S1 is bent toward the second straight line L2.

[0079] The non-reciprocal circuit element 101A of the first modification example has the shortest width W1 shorter than the width W2 , and thus can achieve the same effects as those of the non-reciprocal circuit element 100 .

[0080] Figure 7 1 is a top view of a non-reciprocal circuit element 101B of the second modification. The non-reciprocal circuit element 101B of the second modification is different from the non-reciprocal circuit element 101 in the top view shape of the metal layer 10 in the z direction. Figure 7 In the figure, the same components as those of the non-reciprocal circuit element 101 are denoted by the same reference numerals and their description is omitted.

[0081] The first side S1 of the metal layer 10B is bent toward the third terminal T3 side relative to the first straight line L1. The first side S1 of the metal layer 10B is bent toward the second straight line L2. The first side S1 of the metal layer 10B is bent multiple times.

[0082] The non-reciprocal circuit element 101B of the second modification example has the shortest width W1 shorter than the width W2 , and thus can achieve the same effects as those of the non-reciprocal circuit element 100 .

[0083] Figure 8 1 is a top view of a non-reciprocal circuit element 101C of the third modification. The non-reciprocal circuit element 101C of the third modification is different from the non-reciprocal circuit element 101 in the top view shape of the metal layer 10 in the z direction. Figure 8 In the figure, the same components as those of the non-reciprocal circuit element 101 are denoted by the same reference numerals and their description is omitted.

[0084] The first side S1 of the metal layer 10C is bent toward the third terminal T3 side relative to the first straight line L1. The first side S1 of the metal layer 10C is bent toward the second straight line L2. The first side S1 of the metal layer 10C is bent multiple times. The distance between the first side S1 and the second side S2 may also be the shortest width W1 at multiple locations.

[0085] The non-reciprocal circuit element 101C according to the third modification example has the shortest width W1 shorter than the width W2 , and thus can achieve the same effects as those of the non-reciprocal circuit element 100 .

[0086] Fig. 9 1 is a cross-sectional view of a non-reciprocal circuit element 101D according to a fourth modification. A non-reciprocal circuit element 101C according to the fourth modification is different from the non-reciprocal circuit element 101 in that it includes a resistor 50. Fig. 9 In the figure, the same components as those of the non-reciprocal circuit element 101 are denoted by the same reference numerals and their description is omitted.

[0087] The third terminal T3 of the non-reciprocal circuit element 101 is an open end, but may also be Fig. 9 As shown, the third terminal T3 is connected to the resistor 50. By providing the resistor 50, the absorption characteristics of the high-frequency signal at the third terminal T3 can be further improved. In addition, a grounding conductor may be provided instead of the resistor 50. The grounding conductor electrically connects the first conductor 41, the metal layer 10, and the second conductor 42, and grounds the metal layer 10.

[0088] The non-reciprocal circuit element 101D according to the fourth modification example has the shortest width W1 shorter than the width W2 , and thus can achieve the same effects as those of the non-reciprocal circuit element 100 .

[0089] "Second Implementation Method"

[0090] Fig.101 is a cross-sectional view of a non-reciprocal circuit element 102 of the second embodiment. The non-reciprocal circuit element 102 includes, for example, a metal layer 60, a first loss layer 71, a second loss layer 72, a first magnet 31, a second magnet 32, a first conductor 41, and a second conductor 42. The non-reciprocal circuit element 102 functions as an isolator, for example. The first magnet 31, the second magnet 32, the first conductor 41, and the second conductor 42 are the same as the non-reciprocal circuit element 101 of the first embodiment.

[0091] Fig.11 1 is a plan view of the metal layer 60 and the first lossy layer 71 of the non-reciprocal circuit element 102 according to the second embodiment. Fig.10 It is along Fig.11 The cross section cut along line AA. Fig.12 1 is a plan view of the metal layer 60 of the non-reciprocal circuit element 102 according to the second embodiment. Fig.13 1 is a plan view of the first loss layer 71 of the non-reciprocal circuit element 102 according to the second embodiment.

[0092] The structure of the metal layer 60 is the same as that of the metal layer 10. The metal layer 60 is made of the same material as that of the metal layer 10. The metal layer 60 has a first terminal T1, a second terminal T2, and a third terminal T3. The metal layer 60 has a first region 61 and a second region 62. The first region 61 extends over the first terminal T1 and the second terminal T2. The first region 61 overlaps with the first magnetic body 25 in the z direction. The second region 62 extends between the first terminal T1 and the third terminal T3, and between the second terminal T2 and the third terminal. The second region 62 overlaps with the first absorber 26 in the z direction.

[0093] The first side S1' connecting the first terminal T1 and the second terminal T2 of the metal layer 60 is a straight line without any bends. The first side S1' is a straight line extending along the first straight line L1'. The first straight line L1' is a straight line connecting the first end S1'A ​​and the second end S1'B of the first side S1'.

[0094] The first lossy layer 71 and the second lossy layer 72 sandwich the metal layer 60 in the z direction. The first lossy layer 71 includes a first magnetic body 75 and a first absorber 76. The second lossy layer 72 includes a second magnetic body 77 and a second absorber 78. The first lossy layer 71 and the second lossy layer 72 have substantially the same shape. The first lossy layer 71 has the same material and structure as the first lossy layer 21 except for the shape of the second side S2. The second lossy layer 72 has the same material and structure as the second lossy layer 22 except for the shape of the second side S2.

[0095] The second side S2' of the first absorber 76 is bent toward the first terminal T1 and the second terminal T2 from the second straight line L2'. The second side S2' is bent toward the first straight line L1'. The second straight line L2' is a straight line connecting the first end S2'A and the second end S2'B of the second side S2'.

[0096] The widths of the first side S1' and the second side S2' are, for example, the shortest width W1 at the midpoint P1' of the second side S2'. The midpoint P1' is the center of the second side S2' in the x direction. Here, an example is shown where the shortest width W1 is at the midpoint P1', but the shortest width W1 may also be at a position other than the midpoint P1'.

[0097] The shortest width W1 is shorter than the width W2 between the first straight line L1' and the second straight line L2'. If the shortest width W1 is shorter than the width W2, the cutoff frequency moves to the high frequency side, and the isolation characteristic is not easily reduced even when a high-frequency input signal is input. The shortest width W1 preferably satisfies the above-mentioned formula (1), for example.

[0098] Here, the shortest width W1 between the second side S2 ′ of the first absorber 76 and the first side S1 ′ of the metal layer 60 is described in detail, but the same relationship is preferably satisfied between the second side of the second absorber 78 and the first side S1 ′ of the metal layer 60 .

[0099] In the non-reciprocal circuit element 102 of the present embodiment, since the shortest width W1 is shorter than the width W2, the isolation characteristic is unlikely to be degraded even when a high-frequency input signal is input.

[0100] Although an example of the second embodiment has been described above, the present invention is not limited to these embodiments, and various modifications can be implemented.

[0101] Fig.14 1 is a plan view of a non-reciprocal circuit element 102A according to a fifth modification. Fig.15 1 is a plan view of a non-reciprocal circuit element 102B according to a sixth modification. Fig.16 102 is a top view of a non-reciprocal circuit element 102C according to the seventh modification.

[0102] Similar to the shape of the first side S1 in the first to third modified examples of the first embodiment, the shape of the second side S2' in the first embodiment is also arbitrary. Fig.14 As shown, the second side S2' may also be bent toward the first straight line L1'. Fig.15 and Fig.16 As shown, the second side S2' can also be bent toward the first straight line L1' for multiple times. Fig.16 As shown, the distance between the first side S1 ′ and the second side S2 ′ may be the shortest width W1 at a plurality of locations.

[0103] The non-reciprocal circuit elements 102A, 102B, and 102C according to the fifth to seventh modified examples each have a shortest width W1 shorter than the width W2 , and thus can achieve the same effects as the non-reciprocal circuit element 100 .

[0104] In the second embodiment and its modified example, the third terminal T3 may be an open end, or may be connected to a resistor or a ground conductor.

[0105] Third embodiment

[0106] Fig.17 1 is a cross-sectional view of a non-reciprocal circuit element 103 according to the third embodiment. Fig.18 It is a top view of the non-reciprocal circuit element 103 according to the third embodiment.

[0107] The non-reciprocal circuit element 103 includes, for example, a metal layer 10, a first loss layer 71, a second loss layer 72, a first magnet 31, a second magnet 32, a first conductor 41, and a second conductor 42. The non-reciprocal circuit element 103 functions as an isolator, for example. In the third embodiment, the same reference numerals are given to the same structures as those in the first and second embodiments, and description thereof is omitted.

[0108] The non-reciprocal circuit element 103 of the third embodiment is a combination of the metal layer 10 of the first embodiment and the first loss layer 71 and the second loss layer 72 of the second embodiment.

[0109] The first side S1 of the metal layer 10 is bent toward the third terminal T3 side relative to the first straight line L1. The first side S1 is bent toward the second straight line L2'. The second side S2' of the first absorber 76 is bent toward the first terminal T1 and the second terminal T2 side relative to the second straight line L2'. The second side S2' is bent toward the first straight line L1.

[0110] The shortest width W1 is shorter than the width W2 between the first straight line L1 and the second straight line L2'. If the shortest width W1 is shorter than the width W2, the cutoff frequency moves to the high frequency side, and the isolation characteristic is not easily reduced even when a high-frequency input signal is input. The shortest width W1 preferably satisfies the above-mentioned formula (1), for example.

[0111] Since the shortest width W1 of the non-reciprocal circuit element 103 of this embodiment is shorter than the width W2, the isolation characteristic is not easily degraded even when a high-frequency input signal is input. The non-reciprocal circuit element 103 may be a combination of the first embodiment and the second embodiment.

[0112] Example

[0113] (Example 1)

[0114] Example 1: An example of the first embodiment ( Figure 6 ) is a non-reciprocal circuit element of the same structure. The first side S1 of the metal layer 10 is bent toward the third terminal T3 side relative to the first straight line L1. The second sides S2 of the first absorber 26 and the second absorber 28 are set as straight lines. The width of the first side S1 and the second side S2 is, for example, the shortest width W1 at the midpoint P1 of the first side S1, and the shortest width W1 is shorter than the width W2 between the first straight line L1 and the second straight line L2. The isolation characteristics of the non-reciprocal circuit element of Example 1 with respect to frequency were obtained by simulation.

[0115] (Example 2)

[0116] Example 2: An example of making the same as the second embodiment ( Fig.14 ) A non-reciprocal circuit element of the same structure as in Example 1. The first side S1' of the metal layer 60 is set to be a straight line along the first straight line L1'. The second side S2' of the first absorber 76 and the second absorber 78 is set to be curved toward the first straight line L1'. The width of the first side S1' and the second side S2' is, for example, the shortest width W1 at the midpoint P1' of the second side S2', and the shortest width W1 is shorter than the width W2 between the first straight line L1' and the second straight line L2'. The isolation characteristics of the non-reciprocal circuit element of Example 1 with respect to frequency were obtained by simulation.

[0117] (Comparative Example 1)

[0118] In the non-reciprocal circuit element of Comparative Example 1, the first side S1 of the metal layer 10 is set to a straight line along the first straight line L1, which is different from Example 1, and the second side S2' of the first absorber 76 and the second absorber 78 is set to a straight line along the second straight line L2', which is different from Example 2. The first side S1 and the second side S2 are parallel, and the widths of the first side S1 and the second side are constant. That is, the width W2 of the first side S1 and the second side S2 is consistent with the shortest width W1. The isolation characteristics of the non-reciprocal circuit element of Comparative Example 1 with respect to frequency were obtained by simulation.

[0119] Fig.19 The following are the measurement results of the isolation characteristics of the non-reciprocal circuit elements of Example 1, Example 2, and Comparative Example 1. Fig.19 The horizontal axis is the frequency of the high-frequency signal input to the first terminal T1, and the vertical axis is the isolation characteristic. Fig.19 As shown in FIG. 1 , in Comparative Example 1, the isolation characteristics begin to decrease above 7.5 GHz. In contrast, in Examples 1 and 2, the isolation characteristics do not begin to decrease until around 8.0 GHz. That is, the point at which the isolation characteristics begin to decrease moves toward the high frequency side. Compared with Comparative Example 1, in Examples 1 and 2, the isolation characteristics are not easily decreased even when a high-frequency input signal is input.

Claims

1. A non-reciprocal circuit element, wherein: With: metal layer, loss layer and magnet, The metal layer comprises: a first terminal, a second terminal and a third terminal, The loss layer comprises: a magnetic body and an absorber, The magnetic body overlaps with the first region of the metal layer in the thickness direction, The absorber overlaps with the second region of the metal layer in the thickness direction, the first region extends over the first terminal and the second terminal, The second region extends between the first terminal and the third terminal and between the second terminal and the third terminal, The magnet and the metal layer at least sandwich the magnetic body in the thickness direction. When viewed from the thickness direction, the side of the metal layer connecting the first terminal and the second terminal is set as the first side, and the side of the absorber on the first terminal and the second terminal side is set as the second side. Then, the shortest width of the first side and the second side is shorter than the width between the first straight line connecting the two ends of the first side and the second straight line connecting the two ends of the second side.

2. The non-reciprocal circuit element according to claim 1, wherein: At the midpoint of the first side, the widths of the first side and the second side are the shortest.

3. The non-reciprocal circuit element according to claim 1, wherein: The first side is bent or curved toward the second straight line.

4. The non-reciprocal circuit element according to claim 1, wherein: The second side is bent or curved toward the first straight line.

5. The non-reciprocal circuit element according to claim 1, wherein The first side is bent or curved toward the second straight line, The second side is bent or curved toward the first straight line.

6. The non-reciprocal circuit element according to claim 1, wherein The shortest width satisfies the following formula (1): In the formula (1), W1 is the shortest width, f0 is the maximum frequency of the input signal input to the first terminal or the second terminal, ε0 is the dielectric constant of vacuum, μ0 is the magnetic permeability of vacuum, ε eff is the effective dielectric constant of the magnetic body at frequency f0, μ eff It is the effective magnetic permeability of the magnetic body at the frequency f0 when a DC magnetic field is applied from the magnet to the magnetic body.

7. The non-reciprocal circuit element according to claim 1, wherein: The third terminal is connected to ground via a resistor or directly to ground.

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