Electromagnetic signal processor forming localized regions of magnetic wave energy in gyro-magnetic material

Claim 2

Apparatus for processing electromagnetic wave energy, that comprises, a gyromagnetic material capable of converting electromagnetic excitation wave energy to magnetic wave energy therein, means for exciting the gyromagnetic material with electromagnetic wave energy for conversion to magnetic wave energy in the material, means for applying a magnetic field to the gyromagnetic material and creating therein a non-uniform internal magnetic field profile having a predetermined magnetic field gradient sufficient to confine magnetic wave energy in the material to at least one localized region of the gyromagnetic material that has a dimension that is small relative to the corresponding dimension of the material, and means for extracting from the gyromagnetic material electromagnetic wave energy that has been proposed as the result of the confinement of the magnetic wave energy in the gyromagnetic material.

Claim 3

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines magnetic wave energy in the gyromagnetic material to at least one localized region of magnetic wave energy resonance.

Claim 4

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines magnetic wave energy in the gyromagnetic material to propagation along at least one localized path in the gyromagnetic material.

Claim 5

Apparatus as claimed in claim 1, wherein the magnetic field applying means has a configuration that forces the creation of the non-uniform internal magnetic field profile.

Claim 6

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile comprises at least one magnetic discontinuity in the material.

Claim 7

Apparatus as claimed in claim 5, wherein the discontinuity is a natural discontinuity in the gyromagnetic material.

Claim 8

Apparatus as claimed in claim 5, wherein the discontinuity is formed by a dopant in the gyromagnetic material.

Claim 9

Apparatus as claimed in claim 5, wherein the discontinuity comprises a surface extending internally of the gyromagnetic material.

Claim 10

Apparatus as claimed in claim 8, wherein the surface defines a groove in the gyromagnetic material.

Claim 11

Apparatus as claimed in claim 9, wherein the groove has approximately rectangular cross-sectional configuration.

Claim 12

Apparatus as claimed in claim 10, wherein the depth of the groove is greater than its width.

Claim 13

Apparatus as claimed in claim 9, wherein the exterior surface and the groove surface of the gyromagnetic material are highly polished.

Claim 14

Apparatus as claimed in claim 9, wherein the groove forms a closed loop and the exciting and extracting means are coupled to circumferentially spaced portions of the groove.

Claim 15

Apparatus as claimed in claim 5, wherein the discontinuity defines a track for guiding magnetic wave energy.

Claim 16

Apparatus as claimed in claim 14, wherein the track is a closed loop.

Claim 17

Apparatus as claimed in claim 15, wherein the exciting means and the extracting means are strip electrodes disposed in close proximity to the exterior surface of the gyromagnetic material and extending across the track.

Claim 18

Apparatus as claimed in claim 15, wherein the exciting means produces magnetic wave energy along the track with a wave length that is a submultiple of the perimeter of the track.

Claim 19

Apparatus as claimed in claim 14, wherein the exciting means and the extracting means are coupled to spaced regions of the track.

Claim 20

Apparatus as claimed in claim 5, there being a plurality of said magnetic discontinuities.

Claim 21

Apparatus as claimed in claim 19, wherein each discontinuity defines a track for guiding magnetic wave energy.

Claim 22

Apparatus as claimed in claim 1, wherein the exciting means produces magnetic wave energy that propagates in the gyromagnetic material with minimal surface scattering.

Claim 23

Apparatus as claimed in claim 1, wherein the exciting means produces magnetic wave propagation in the gyromagnetic material that is non-reciprocal.

Claim 24

Apparatus as claimed in claim 1, wherein the exciting means produces magnetic wave propagation in the gyromagnetic material having a pedetermined propagation direction and group velocity.

Claim 25

Apparatus as claimed in claim 1, wherein the exciting means and the extracting means comprise first and second parallel strip electrodes, respectively, disposed at the same side of the gyromagnetic material.

Claim 26

Apparatus as claimed in claim 24, wherein the electrodes are separated from one another by no more than of the order of a few hundred micrometers.

Claim 27

Apparatus as claimed in claim 24, wherein a grounded strip is interposed between the electrodes.

Claim 28

Apparatus as claimed in claim 1, wherein the exciting means and the extracting means comprise electrode means substantially at the exterior surface of the gyromagnetic material and wherein the efficiency of energy transfer to and from the gyromagnetic material is very sensitive to the position of the electrode means relative to said external surface.

Claim 29

Apparatus as claimed in claim 1, wherein the exciting means excites the gyromagnetic material with electromagnetic wave energy having a predetermined frequency spectrum and wherein the extracting means extracts electromagnetic wave energy having a different frequency spectrum resulting from the confinement of magnetic wave energy in the gyromagnetic material.

Claim 30

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines magnetic wave energy in the gyromagnetic material to at least one localized region of magnetic wave energy resonance, and wherein the magnetic wave energy resonance in the gyromagnetic material is sufficient to provide a high-Q filter between the exciting means and the extracting means.

Claim 31

Apparatus as claimed in claim 1, wherein the magnetic field applying means magnetizes the gyromagnetic material to saturation.

Claim 32

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines magnetic wave energy in the gyromagnetic material to a plurality of localized physically separated regions of the material.

Claim 33

Apparatus as claimed in claim 31, wherein the exciting means and the extracting means comprise input and output electrodes at each of the physically separated regions.

Claim 34

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines magnetic wave energy in the gyromagnetic material to a plurality of physically separated localized regions of magnetic wave energy resonance.

Claim 35

Apparatus as claimed in claim 1, wherein the gyromagnetic material has non-ellipsoidal geometry.

Claim 36

Apparatus as claimed in claim 1, wherein the gyromagnetic material comprises a rectangular slab.

Claim 37

Apparatus as claimed in claim 1, wherein the gyromagnetic material is a single crystal YIG.

Claim 38

Apparatus as claimed in claim 1, wherein the gyromagnetic material is highly polished at at least selected parts of its exterior surface.

Claim 39

Apparatus as claimed in claim 1, wherein the means for applying a magnetic field and creating a non-uniform magnetic field profile confines the magnetic wave energy to regions at or near the exterior surface of the gyromagnetic material.

Claim 40

Apparatus as claimed in claim 1, wherein the exterior surface of the gyromagnetic material has predetermined lossy areas affecting the propagation of magnetic wave energy.

Claim 41

Apparatus as claimed in claim 39, wherein the lossy areas are roughened to render them lossy.

Claim 42

Apparatus as claimed in claim 1, wherein the gyromagnetic material has means for suppressing undesired modes of propagating magnetic wave energy.

Claim 43

Apparatus as claimed in claim 41, wherein the suppressing means comprises a dopant.

Claim 44

Apparatus as claimed in claim 35, wherein the suppressing means comprises a mask.

Claim 45

Apparatus as claimed in claim 1, wherein the gyromagnetic material is a single crystal thin film.

Claim 46

Apparatus as claimed in claim 1, wherein the gyromagnetic material is a single crystal thick film.

Claim 47

Apparatus as claimed in claim 1, wherein the gyromagnetic material is polycrystalline.

Claim 48

Apparatus for processing electromagnetic wave energy, that comprises, a gyromagnetic material capable of converting electromagnetic excitation wave energy to magnetic wave energy therein, means for introducing electromagnetic excitation wave energy to the gyromagnetic material for conversion to magnetic wave energy in the material, means for applying a magnetic field to the gyromagnetic material and creating therein a non-uniform internal magnetic field profile having a predetermined field gradient sufficient to control at least one magnetic wave energy parameter in the gyromagnetic material by field gradient confinement of magnetic wave energy in the material to at least one localized region of the gyromagnetic material having a dimension that is small relative to the corresponding dimension of the material, and means for extracting from the gyromagnetic material electromagnetic wave energy that has been processed as the result of the control of said parameter in the gyromagnetic material.

Claim 49

Apparatus for processing electromagnetic wave energy, that comprises, a gyromagnetic material capable of converting electromagnetic excitation wave energy to magnetic wave energy therein, means for introducing electromagnetic excitation wave energy to the gyromagnetic material for conversion to magnetic wave energy in the material, means for applying a magnetic field to the gyromagnetic material and creating therein a non-uniform internal magnetic field profile having a predetermined field gradient sufficient to control at least one magnetic wave energy parameter in the gyromagnetic material by field gradient confinement of magnetic wave energy in the material to at least one localized region of the gyromagnetic material having a dimension that is small relative to the corresponding dimension of the material, and means for extracting from the gyromagnetic material electromagnetic wave energy that has been processed as the result of the control of said parameter in the gyromagnetic material.

Claim 52

A method as claimed in claim 48, wherein the field gradient confinement confines magnetic wave energy to at least one localized region of magnetic wave energy resonance.

Claim 53

A method as claimed in claim 49, further comprising adjusting the applied magnetic field to adjust the frequency of the resonance.

Claim 54

A method as claimed in claim 48, wherein the field gradient confinement confines magnetic wave energy to propagation along at least one localized path.

Claim 55

A method as claimed in claim 48, wherein the introduction of electromagnetic excitation wave energy is restricted to a localized region of the gyromagnetic material.

Claim 56

A method as claimed in claim 48, wherein the magnetic wave energy propagation is two dimensional and in which magnetic wave energy parameters are interrelated to the magnetic field gradient by an expression of the type ##EQU12## in an x-y-z local coordinate system defined so that the local direction of magnetic wave propagation is in the y-direction and in which the wave pattern within the gyromagnetic material is substantially independent of the coordinate z; where Z=H z /M is the z-component of the internal magnetic field normalized to the saturation magnetization; Ω=ω/ω M , where ω is the radian frequency of the magnetic wave energy, ω M =-γμ o M, where γ is the gyromagnetic ratio which is negative for electrons, μ o =4π×10 -7 Henries/meter; k is the wavenumber of the magnetic wave energy, k=(2π/λ), where λ is the wavelength at the position x; and p(x) describes the x variation of the magnetostatic potential exponential (∫p(x)dx).