Sensor system for capturing an environment

Abstract

TITLE: "Sensor System for Sensing a Medium" Magnetic field sensor (1) comprising a magneto-optical material (2), a light excitation source (3) for emitting radiation to excite the electronic states of the magneto-optical material (2), a microwave source (4) for generating an electromagnetic field to power a resonator structure (8), and a detector (5) of the fluorescent radiation from the magneto-optical material (2) following the excitation radiation. A magnetic field generator device (6) generates a permanent magnetic field in the region of the magneto-optical material (2). A resonator structure (8) mounted on a dielectric (7) shapes the electromagnetic field emitted by the microwave source (4) to generate a microwave field to manipulate the spin states of the magneto-optical material (2).The magneto-optical material (2), the light excitation source (3), the detector (5) and the microwave structure (8) are in a closed space (9). Figure 1.

Description

Title of the invention: “Sensor system for capturing a medium” FIELD OF THE INVENTION

[0001] The present invention relates to a magnetic field sensor based on an NV-center diamond. STATE OF THE ART

[0002] For some years now, diamond crystals have been known whose lattice has defects in the form of NV centers and are the subject of research. In an NV center, a nitrogen atom is at the lattice location of a carbon atom and in the immediate vicinity of the nitrogen atom, the location of a lattice carbon atom, has a vacancy. If such a crystal lattice is excited with excitation radiation of a wavelength between 490nm and 575nm, electron transfer from a 3A2 ground state to a 3E excited state is induced in the crystal lattice. From this 3E excited state, the NV center relaxes by the emission of fluorescent radiation in a wavelength range between 600nm and 850nm to return to the 3A2 ground state.

[0003] The ground state 3A2 has three magnetic substates with ms=0, ms=±l. The states ms=0 and ms=±l differ by an energy difference of 2.87 GHz (zero field splitting). The excited state 3E also has three magnetic substates with ms =0, ms=±l. If then the NV-center of the ground state 3A2 is moved into a magnetic alternating field at a frequency of 2.87 GHz (usually) and in the following alternating magnetic fields in a frequency range between 1 and 4 GHz are used as a "microwave field". The NV-center oscillates between the ground state ms=0.3A2 and the ground state ms=±l, 3A2. When irradiated with exciting radiation the NV-center is only partially moved from its ground state ms=±l, 3A2 into the excited state ms=±l, 3E. From there it relaxes mainly without emitting radiation to return to the ground state. If we measure the intensity of the fluorescent radiation as a function of the frequency of the microwave field, we obtain for a frequency of 2.87 GHz, a sharp drop in the intensity of fluorescent radiation (called a peak). The drop in the intensity of fluorescent radiation can be explained by the fact that for incident radiation from the microwave field with a frequency of 2.87 GHz, fewer NV centers are available in the ground state ms=0.3A2 that can be excited optically and which can relax to the ground state ms=±1.3A2 by the emission of fluorescent radiation.

[0004] In an external magnetic field, the ground state ms=±l, 3A2 splits with the quantum numbers ms=l and ms=-l by the Zeemann effect. If the intensity of the fluorescent radiation is then measured using the frequency of the microwave field, two peaks are obtained. The frequencies at which these peaks occur depend on the extent of the splitting in the ground state ms=±l, 3A2 and thus on the intensity of the external magnetic field.

[0005] Such a magnetic field sensor is known from DE 10 2020 204 732. According to this document, the excitation radiation is generated with a laser diode, installed in a cavity. The cavity is obtained by the hollowing out of a support plate and a glass substrate hermetically closing the cavity. The excitation radiation is conducted through a glass substrate into a plane located below in which an NV diamond is focused. The lower plane has a substrate carrying the other components of the system such as the diamond, a high-frequency installation, photodetectors and other optical components. The substrate closes with a cover which has an opening through which the excitation radiation falls on the diamond. The laser diode can thus be installed separately from the other components of the magnetic field sensor in a closed space of its own.Such a magnetic field sensor with two separate cavities is bulky and cannot be miniaturized. In addition, the alternating magnetic field generated by the high-frequency installation is freely deployed, so that the characteristic of the high-frequency installation will be influenced by the materials of an environment of the magnetic field sensor. Thus, the specificity of the magnetic field sensor may be influenced, which does not allow the magnetic field sensor to be used universally. In addition, the components outside the magnetic field sensor may be disturbed by the alternating magnetic field, and the electromagnetic compatibility of the magnetic field sensor will be reduced.

[0006] PURPOSE OF THE INVENTION

[0007] The aim of the present invention is to develop a magnetic field sensor making it possible to overcome the drawbacks of the state of the art.

[0008] DISCLOSURE AND ADVANTAGES OF THE INVENTION

[0009] To this end, the invention relates to a magnetic field sensor comprising:

[0010] - a magneto-optical material,

[0011] - a light excitation source for emitting excitation radiation for excite the electronic states of magneto-optical matter,

[0012] - a microwave source for generating an electromagnetic field for power a resonator structure,

[0013] - a detector for capturing the fluorescent radiation emitted by the magneto-material optical following excitation radiation,

[0014] - a magnetic field generating device which generates a magnetic field permanent in the area of ​​magneto-optical matter,

[0015] - a resonator structure installed on a dielectric and which forms the field electromagnetic emitted by the microwave source to generate a microwave field which allows the spin states of the magneto-optical matter to be manipulated,

[0016] - sensor in which,

[0017] the magneto-optical material, the light excitation source, the detector and the microwave structure are in a closed space.

[0018] In other words, the subject of the invention is a magnetic field sensor for capturing a magnetic field and which comprises a magneto-optical material, an excitation light source, a microwave source and a detector. The magneto-optical material is a diamond crystal whose crystal lattice has vacancies in the form of NV-centers. The excitation light source emits excitation radiation to excite the electronic states of the magneto-optical material. The excitation light source is an iodine laser with a wavelength between 490nm and 575nm. The microwave source generates an electromagnetic field which powers a resonator structure, i.e. a resonator structure. The detector captures the fluorescent radiation emitted by the magneto-optical material under the effect of its irradiation with the excitation radiation.In addition, the magnetic field sensor has a magnetic field generating device installed and made to generate a permanent magnetic field in the area of ​​the magneto-optical material.

[0019] The resonator structure is installed on a dielectric; it is designed to amplify the electromagnetic field generated by the microwave source in at least one predefined frequency band to develop a homogeneous microwave field in the region of the magneto-optical material. Thus, the generated microwave field makes it possible to manipulate the spin states of the magneto-optical material and corresponds, for example, to one or more frequencies in a frequency band of 2.5 GHz and 3 GHz.

[0020] The deposition of organic substances on optical components, especially on the excitation light source, is a problem. To protect the magneto-optical material, the excitation light source, the detector and the resonator structure from other environmental influences, these elements are housed in a closed enclosure. The magneto-optical material, the excitation light source and the detector can also be on a dielectric. The installation of the magneto-optical material, the excitation light source, the detector and the structure of resonator in a closed enclosure, in particular airtight, allows the compact magnetic field sensor to be produced. In addition, the spatial proximity of the resonator structure to the magneto-optical material means that the microwave field amplified and formed by the resonator structure will be effective and can be coupled with the magneto-optical material with practically no loss.

[0021] Thus a first metal layer is under the resonator structure installed on the dielectric and a second metal layer is provided above the dielectric installed on the resonator structure. The first and second metal layers shield the microwave field amplified and formed by the resonator structure, from above and below the closed enclosure. In addition, the first and / or second metal layers develop a reinforced microwave field for the resonator structure.

[0022] In this way, both the microwave field is protected from the environment of the enclosed space and also the electronic and optical components of the magnetic field sensor from environmental conditions.

[0023] The first and / or second metal layer are mass surfaces connected to the electrical ground of the microwave source. The wave impedance, shape and deployment speed of the electromagnetic microwave field can be influenced, among other things, by the material of the dielectric and by the position of the first and / or second metal layer connected to the ground.

[0024] The resonator structure comprises an electroconductive structure on the dielectric and for example an omega resonator as a planar slot waveguide structure or an open loop resonator. The resonator structure forms a resonator in common with the dielectric which carries it and the first and / or second metal layer as a ground surface. The wave impedance, the shape and the speed of deployment of the electromagnetic microwave field depend among other things on the material of the dielectric and the position of the first and second metal layers connected to the ground. The geometry of the resonator is chosen to generate the microwave field so that the area in which the magneto-optical material is located is homogeneous and limited to this local area. The resonator is in particular designed to amplify frequencies in one or more frequency bands in a range between 2.5 and 3.1 GHz.Outside these frequency bands, it may happen that the efficiency of field generation decreases so sharply that the power of the microwave source is no longer sufficient for useful operation of the magnetic field sensor.

[0025] Compared to a wire usually used, traversed by the current and which is installed close to the magneto-optical material, the use of the resonator structure has the advantage of generating a very efficient microwave field. Thus the source of micro waves will have only low power and its corresponding dimensioning will be small, thus allowing the production of a compact magnetic field sensor.

[0026] According to a development of the invention, the base surface and the four side surfaces are formed on a single, in particular intelligent, housing, the housing having at least one dielectric as a base surface and the resonator structure being installed on this base surface. The housing is closed by a separate cover, the side facing the components of the magnetic field sensor having a top surface. According to this development of the invention, the four side surfaces, the bottom surface and the top surface delimit a closed space. The housing can be made entirely or partly of a dielectric, for example of a dielectric plastic material. The use of a housing facilitates the manufacture of the magnetic field sensor because such a housing, called packaging, is simple and available.

[0027] According to a development of the invention, the magnetic field sensor has a closure, in particular a single-part closure, and the top surface and the four side surfaces are formed on the closure. In this case, the base surface can be produced on an electrical substrate. The resonant structure is in particular installed on the base surface, which in this case is installed on the first dielectric substrate. The first dielectric substrate has a dielectric or is completely or partially made of a dielectric, for example a dielectric plastic material. Even for this development of the invention, the four side surfaces, the base surface, and the top surface delimit a closed volume. The closure of such a volume is carried out in a simple and economical manner, so that such a magnetic field sensor is economical and simple.

[0028] According to a development of the invention, the housing or the first dielectric substrate are on a circuit board. Between the circuit board and the housing or the circuit board of the first dielectric substrate there is a gap associated with the first dielectric substrate. This gap can be filled with air or a dielectric material. The installation of the housing on the first dielectric substrate of the circuit board allows a particularly simple connection of the components of the magnetic field sensor installed in the enclosed space and also the simple mounting of the magnetic field sensor.

[0029] The thickness of the gap can influence the impedance of the resonator and the speed of the microwave field deployment so that the resonance frequency is influenced. Even a small variation in the thickness of the gap can change the resonance frequency very significantly up to a resonance frequency at which the magnetic field sensor can no longer function advantageously.

[0030] The housing or the first dielectric substrate can also be directly on the circuit board which allows simple and economical manufacturing of the magnetic field sensor.

[0031] According to a development of the invention, the resonator structure is also surrounded by a third metal layer on the dielectric. The third metal layer is installed to surround the resonator structure on four lateral surfaces, completely or partially by the third metal layer. The third metal layer is connected to the electrical ground of the microwave source. The sensitivity of the resonant frequency with respect to the thickness of the gap can be decreased by installing the third metal layer on the dielectric around the resonator structure.

[0032] According to a development of the invention, the resonator structure is on the side of the first dielectric substrate facing the closed enclosure and the first metal layer is on an opposite side of the first dielectric substrate. In particular, the first dielectric substrate is in the housing and the first metal layer is on the side of the first dielectric substrate facing the base surface of the housing, the resonator structure being on the side of the dielectric substrate not facing the base surface of the housing (and thus closer to the closed space). In this development of the invention, the sides of the dielectric substrate not facing the base surface, the four side walls and the top surface made on the cover constitute a closed space. The first dielectric substrate can thus be totally or partially made of a dielectric material, for example an electrical plastic material.Such an embodiment allows simple mounting and thus economical installation of the magnetic field sensor.

[0033] According to a development of the invention, the second metal layer is on a second dielectric substrate. This second dielectric substrate is in particular installed on the top surface of the cover, the second metal layer being on the side of the second dielectric substrate facing the top surface (and thus facing the enclosed space). In addition or alternatively, a fourth metal layer is provided facing the second metal layer and thus on the side of the second dielectric substrate which is opposite the top surface. Such an embodiment allows simple and thus economical mounting of the magnetic field sensor.

[0034] According to a development of the invention, the first metal layer is a cooling block which allows a particularly compact construction of the magnetic field sensor because any additional cooling block or an additional metal layer is avoided.

[0035] According to a development of the invention, parallel to one of the lateral surfaces of the closed space, a fifth metallic layer improves the protection of the field microwave amplified by the resonator structure. This fifth metal layer can be connected to the second and / or the first metal layer and / or also connected to another metal layer for example by electrical contacts.

[0036] The resonator structure can be made by a laser or be structured by laser. This allows the resonator structure to be made in a simple, precise and economical manner. Brief description of the drawings

[0037] The present invention will be described below in more detail with the aid of embodiments shown in the accompanying drawings in which:

[0038] [Fig-1] embodiment of a magnetic sensor according to the invention whose magneto-optical material, the light excitation source, the detector and the resonator structure are on a dielectric in a closed space,

[0039] [Fig.2] another example of embodiment of a magnetic field sensor according to the invention whose magneto-optical material, the light excitation source, the detector and the resonator structure are on the base surface of a housing under which there is a metal layer,

[0040] [Fig.3] another example of embodiment of a magnetic field sensor according to the invention, the magneto-optical material, the light excitation source, the detector and the resonator structure of which are on a first dielectric substrate,

[0041] [Fig.4] another example of embodiment of a magnetic field sensor according to the invention, the sensor having a second dielectric substrate in addition to the first dielectric substrate,

[0042] [Fig.5] another example of embodiment of a magnetic field sensor according to the invention with a metal layer in the form of a cooling block,

[0043] [Fig.6] another example of embodiment of the magnetic field sensor according to the invention comprising metal layers on its lateral surfaces,

[0044] [Fig.7] another example of embodiment of a magnetic field sensor according to the invention, the metal layers of the side surfaces of which are connected to the metal layers of the base surface and the top surface,

[0045] [Fig.8] Embodiment of a magnetic field sensor in top view.

[0046] DESCRIPTION OF AN EMBODIMENT

[0047] [Fig.l] shows a magnetic field sensor 1 whose magneto-optical material 2, for example a diamond with NV point defects, as well as an excitation light source 3, for example in the form of a laser diode, and a detector 5 are installed on a dielectric 7. A resonator structure 8 is also installed on the dielectric. This structure amplifies and shapes an electromagnetic alternating field of a predefined frequency band, generated by a source of microwaves so as to develop a microwave field, homogeneous in the area of ​​the magneto-optical material 2. [Fig.l] shows the field lines of the microwave field 41. A first metal layer 11 is applied against the lower side of the dielectric 7. The excitation light source 3, the magneto-optical material 2 and the detector 5 are thus in a closed space.

[0048] The excitation light source 3 is designed to emit excitation radiation with a wavelength between 490nm and 575nm. When the magneto-optical material 2 is illuminated by the excitation radiation, which excites an electronic state of the magneto-optical material 2 which relaxes back to the ground state by the emission of fluorescent radiation. The microwave field of a suitable frequency, for example 2.87 MHz, simultaneously excites the spin states of the magneto-optical material 2 so that the intensity of the emitted fluorescent radiation decreases because the ground state from which the excitation passes into an excited state is occupied with a lower probability. The intensity of the fluorescent radiation can be captured by the detector 5.

[0049] A microwave field is generated with an alternating electromagnetic field amplified by the resonator structure 8 on the dielectric 7 and this field is shaped to have a microwave field 41 at the location of the magneto-optical material 2. The first metal layer 11 delimits the microwave field 41 downwards 13 but not upwards 12 so that it can develop freely upwards. As a result, the characteristic of the microwave field 41 generated by the resonator structure 8 can thus be influenced by the environment of the magnetic field 1 and the magnetic sensor 1 cannot be universally applied. Furthermore, components outside the magnetic field sensor 1 could also be disturbed by the microwave field 41 thus generated so that such magnetic sensors 1 would not meet the requirements of electromagnetic compatibility.

[0050] In addition, the optical and electro-optical components 2, 3, 5, 8 of the magnetic field sensor 1 are exposed to environmental conditions. This constitutes a problem in particular for the excitation light source 3. If this is a laser diode, all facets of the laser diode are sensitive to organic deposits.

[0051] [Fig. 2] shows an exemplary embodiment of a magnetic field sensor according to the invention. The base surface 14 of the housing 17 carries a resonator structure 8, the magneto-optical material 2 for example a diamond crystal with NV point defects, the excitation light source 3 for example a laser diode and a detector 5. The housing 17 has four side surfaces of which two side surfaces 15, 16 are shown in [Fig. 2] and the base surface 14. The housing 17 is in one part and at least its base surface 14 has a dielectric 7. The housing 17 can also be completely or practically completely in a dielectric 7. The resonator structure 8 is installed directly on the base surface 14 in particular directly on the dielectric 7.

[0052] A first metal layer 10 is under the base surface 14 of the housing 17 and thus under the resonator structure 8, in particular parallel to the base surface 14. Another metal layer 11 is above the resonator structure 8 in particular on one of the sides of a cover surface 18 facing the components of the magnetic field sensor 2, 3, 5, 8. There is thus a microwave field 41 protected by the first and second metal layers 10, 11 with respect to the upper side 12 and the lower side 13 of a closed volume 9 delimited by the top surface 18, the four side walls 15, 16 and the base surface 14. But it could also be possible to have only a single metal layer 10, 27, 30 under the base surface 14 of the housing 17 and even the existence of a single metal layer achieves a sufficient shielding and shaping of the microwave field.

[0053] The top surface 18 is formed on a cover 33 so that the cover 33 and the housing 17 close from the outside the closed volume 9 of the excitation light source 3, the detector 5 and the electromagnetic field 2 as well as the resonator structure 8. Thus the excitation light source 3 and the detector 5 are protected against environmental influences such as, for example, dirt. At the same time, the resonator structure 8 can be in the immediate vicinity of the magneto-optical material 2 so that the microwave field generated by the resonator structure 8 is transmitted losslessly or practically losslessly to the magneto-optical material 2.

[0054] The resonator structure 8 can, as shown in [Fig. 2], be surrounded by a third metal layer 20 on the base surface 14. The housing 17 is on a circuit board 24 and in particular the housing 17 is welded to the circuit board 24. There is thus a gap 25 between the circuit board 24 and the housing 17. This gap 25 is filled with air or preferably with a dielectric material. In the absence of the metal layer 17 and 27, the thickness of the gap 25 between the housing 147 and the circuit board 24 influences the wave impedance of the resonator formed by the resonator structure 8, the dielectric 7 as well as the first and second metal layers 11, 30 as well as the deployment speed of the developing wave and thus the resonant frequency of the resonator. The existence of the third metal layer 20 can reduce the sensitivity of the resonance frequency to a variation in the thickness of the gap 25.

[0055] One or more other metal layers 27 may be provided under the first metal layer 10 or as a variant of the first metal layer 10 in the housing 17, in particular parallel to the base surface 14 of the housing 17. The one or more metal layers 27 may alternatively or additionally be on the outer side of the housing 17. Likewise above the second metal layer or alternatively of this second metal layer 11, there may be further metal layers 28, 29 in the cover 33 in particular parallel to the base surface 14 and / or to the cover surface 18 or on the side of the cover 33 opposite the sensor components 2, 3, 5, 8, i.e. on the outer side of the cover 33.

[0056] It is also possible to have metal layers 30, 31, 32 on the circuit board 24. These metal layers 30, 31, 32 are on one or both sides and / or in the circuit board 24. The circuit board 24 can also be connected to the microwave source 4, to the resonator structure 8 and to the magnetic field generating device 6. This magnetic field generating device 6 can comprise a Helmholtz coil and / or one or more permanent magnets generating a permanent magnetic field in the area of ​​the magneto-optical material 2.

[0057] The metal layers 10, 11, 27, 28, 29, 30, 31, 32 may be grounding surfaces and be connected to the electrical ground of the microwave source 4.

[0058] [Fig. 3] shows another embodiment of magnetic field sensor 1. In contrast to the embodiment of [Fig. 2], the four side surfaces 15, 16 as well as the top surface 18 of the closed space 9 receiving the excitation light source 3, the detector, the magneto-optical material 2 and the resonator structure 8 are formed on a closure 19. The base surface 14 is formed on the first dielectric substrate 21. The first dielectric substrate 21 has a dielectric 7. The closure 19 is installed directly on the first dielectric substrate 21. As is apparent in the embodiment of [Fig. 2], in this case also the excitation light source 3, the detector 5, the resonator structure 8, the magneto-optical material 2 and the third metal layer 20 are on the base surface 14. The third metal layer 20 surrounds the resonator structure 8.

[0059] The first metal layer 10 may be in the dielectric substrate 21. The second metal layer 11 is provided on the top surface 18 of the closure 17 so that it faces the components 2, 3, 5, 8 of the magnetic field sensor 1. Further metal layers 28, 29 are provided in or on the closure 17, for example, parallel to the top surface 18. The dielectric substrate 21 may also be provided analogously to the embodiment described in [Fig. 2] on a circuit board 24 not shown in [Fig. 3].

[0060] [Fig. 4] shows another embodiment of the magnetic field sensor 1 according to the invention. In this case, the first dielectric substrate 21 and a second electrical substrate 22 are provided in the housing 17. The first metal layer 10 is on the base surface 14 of the housing 17 and the first dielectric substrate 21 is on the first metal layer 10. The resonator structure 8 as well as the third metal layer 20 are provided on the first dielectric substrate 21.

[0061] The top surface 18 of the cover 33 is provided, inside the closed space 9, with a fourth metal layer 23, the side of which facing the closed space 9 is provided with the second dielectric substrate 22. The side facing the closed space 9 of the second dielectric substrate 22 is provided with a second metal layer 11. In this embodiment, the dielectric 7 is formed by the first dielectric substrate 21. The housing 17 can, in a manner analogous to the embodiment described with the aid of [Fig. 2], be on a circuit board 24 not shown in [Fig. 4].

[0062] [Fig.5] shows another embodiment of the magnetic field sensor 1. As in the embodiment of [Fig. 2], the resonator structure 8, the excitation light source 3, the detector 5 and the magneto-optical material 2 are on the base surface 14 of the housing 17. The third metal layer 20 can also be on the base surface 14 of the housing 17. The top surface 18 of the cover 33 is provided with the second metal layer 11. The first metal layer 10 is under the base surface 14 in the housing 17 in particular parallel to the base surface 14 and constitutes a cooling block 25. This cooling block 25 can be made of an electrically conductive material. The cooling block 25 is connected to the electrical ground of the microwave source 4 and serves as a screen and / or grounding surface. In this exemplary embodiment, the housing 17 may comprise a circuit board 24 not shown in [Fig. 5], in a manner analogous to the embodiment described in connection with [Fig. 2].

[0063] [Fig. 6] shows another embodiment of the magnetic field sensor 1. In this case too, the resonator structure 8, the excitation light source 3, the detector 5 and the magneto-optical material 2 are on the base surface 14 of the housing 17. The third metal layer 20 can also be on the base surface 14 of the housing 17. The second metal layer 11 is in or on the cover 23 in particular parallel to the top surface 18. The first metal layer 10 is under the base surface 14 in the housing 17 in particular parallel to the base surface 14. At least one of the side surfaces 15, 16 is provided with a fifth metal layer 26. Further metal layers 33, 35 can be on the housing 17 or the closure 19 or on one of the outer sides of the housing 17 or the closure 19, each time parallel to one of the lateral surfaces 15, 16.The metal layers 26, 34, 35 cut the microwave field relative to the environment of the magnetic field sensor 1. Similarly to the embodiment of [Fig.2], in this exemplary embodiment, the housing 17 may be on a circuit board 24 not shown in [Fig.6].

[0064] [Fig. 7] shows another embodiment of the magnetic field sensor 1. This embodiment according to [Fig. 7] corresponds to the embodiment of [Fig. 6] with parallel to one of the side surfaces 15, 16 metal layers 26, 34, 35 parallel to the base surface 14 or to the metal layers 10, 27 in the housing 17 and / or be connected to one or the other metal layer 11, 28, 29 associated with the cover 33. The metal layers 26, 34, 35 parallel to one of the side surfaces 15, 16 can be connected by a conductive connection via the contacts 34, 37, 38 to the metal layers 11, 28, 29 passing in or around the cover 33.

[0065] In an embodiment in which the side surfaces 15, 16 and the top surface 17 are provided on the closure 19 and the base surface 14 on a dielectric substrate 21, parallel to one of the layers 26, 34, 35 may be side surfaces 15, 16 (in this case in the closure 19). The metal layers 26, 34, 35 parallel to one of the side surfaces 15, 16 can be electrically connected to the metal layers 10, 27 provided in or on the dielectric substrate 21 and / or to the metal layers 11, 28, 29 installed parallel to the top surface 18 or in or on the closure 19. In this case, the electrical connection of the metal layers 10, 27, provided in or on the dielectric substrate 21 is made with the metal layers 26, 34, 35 parallel to one of the side surfaces 15, 16 by the contacts 26, 37, 38.

[0066] [Fig. 8] shows an embodiment of the magnetic field sensor 1 in top view. The resonator structure 8, the excitation light source 3 and the magneto-optical material 2 are on the base surface 14 of the housing 17. The cover 33, which closes the space closed in common with the housing 17 from the outside, is not shown in [Fig. 8]. The resonator structure 8 has a first horseshoe-shaped part 39 and an annular second part 40; both the first horseshoe-shaped part 39 and the second annular part 40 have a slot whose respective edges connect the two parts 39, 40 to each other. In the center of the second annular part 40 is the magneto-optical material 2 (in this case the diamond with the NV defect points). The housing 17 is on a circuit board 24. The circuit board 24 is also provided with the magnetic field generating device 6 which is in the form of an installation of four permanent magnets.

[0067] NOMENCLATURE OF MAIN ELEMENTS

[0068] 1 Magnetic field sensor

[0069] 2 Magneto-optical matter

[0070] 3 Excitation light source

[0071] 4 Microwave source

[0072] 5 Detector

[0073] 7 Dielectric

[0074] 8 Resonator structure

[0075] 10 First metal layer

[0076] 11 Second metallic layer

[0077] 12 Upper side

[0078] 13 Lower side

[0079] 14 Base area

[0080] 15 Lateral surface

[0081] 16 Lateral surface

[0082] 17 Housing

[0083] 18 Top surface

[0084] 19 Closing

[0085] 21 First dielectric substrate

[0086] 22 Second dielectric substrate

[0087] 23 Fourth metallic layer

[0088] 24 Circuit board

[0089] 25 Cooling block

[0090] 26 Fifth metallic layer

[0091] 27 Metallic layer

[0092] 28 Metallic layer

[0093] 29 Metallic layer

[0094] 30 Metallic layer

[0095] 31 Metallic layer

[0096] 32 Metallic layer

[0097] 33 Cover

[0098] 34 Metallic layer

[0099] 35 Metallic layer

[0100] 36 Contact

[0101] 37 Contact

[0102] 38 Contact

[0103] 39 First part of the resonator structure

[0104] 40 Second part of the resonator structure

[0105] 41 Microwave field

Claims

Claims

1. A magnetic field sensor (1) comprising: - a magneto-optical material (2), - an excitation light source (3) for emitting excitation radiation for exciting the electronic states of the magneto-optical material (2), - a microwave source (4) for generating an electromagnetic field feeding a resonator structure (8), - a detector (5) for capturing the fluorescent radiation emitted by the magneto-optical material (2) as a result of the excitation radiation, - a magnetic field generating device (6) which generates a permanent magnetic field in the area of ​​the magneto-optical material (2), - a resonator structure (8) installed on a dielectric (7) and which forms the electromagnetic field emitted by the microwave source (4) to generate a microwave field which makes it possible to manipulate the spin states of the magneto-optical material (2), - a sensor in which the magneto-optical material (2), the light excitation source (3),the detector (5) and the resonator structure (8) are in a closed space (9).,

2. Magnetic field sensor (1) according to claim 1, wherein a first metal layer (10) is provided under the resonator structure (8) installed on the dielectric (7), and / or - a second metal layer (11) is provided above the resonator structure (8) itself on the dielectric (7), and the first and / or second metal layer (10, 11) shields the upper side (12) and the lower side (13) of the enclosed space (9) from the microwave field of the microwave structure (8).

3. Magnetic field sensor (1) according to claim 1, wherein a bottom surface (14) as well as four side surfaces (15, 16) of the closed volume (9) are formed in a housing (17), - the housing (17) has a dielectric (7) at least on the base surface (14).

4. A magnetic field sensor (1) according to claim 1, in which the covering surface (18) as well as the four side surfaces (15, 16) of the closed volume (9) are produced on a closure (19), and - the base surface (14) forms a first dielectric substrate (21).

5. A magnetic field sensor (1) according to claim 2 or 3, wherein the resonator structure (8) is on the base surface (14) of the closed volume (9).

6. Magnetic field sensor (1) according to one of the preceding claims, wherein the first and / or the second metal layer (10, 11) are ground surfaces connected to the ground of the microwave source (4).

7. Magnetic field sensor (1) according to one of the preceding claims, wherein the resonator structure (8) is surrounded by a third metal layer (20) also installed on the dielectric (7).

8. Magnetic field sensor (1) according to one of the preceding claims, wherein the resonator structure (8) of the first metal layer (10) is opposite the first dielectric substrate (21).

9. A magnetic field sensor (1) according to any preceding claim, wherein the second metal layer (11) is on a second dielectric substrate (22).

10. The magnetic field sensor (1) of claim 8, wherein a fourth metal layer (23) faces the second metal layer (11) on the second dielectric substrate (22).

11. A magnetic field sensor (1) according to any preceding claim, wherein the housing (17) or the first dielectric substrate (21) are on a circuit board (24).

12. A magnetic field sensor (1) according to claim 10, wherein a gap (25) in particular filled with air or a dielectric material is provided between the circuit board (24) and the housing (17) or between the first dielectric substrate (21).

13. Magnetic field sensor (1) according to one of the preceding claims, wherein the first metal layer (10) is in the form of a cooling block (25).

14. Magnetic field sensor (1) according to one of the preceding claims, wherein a fifth metal layer (26) is parallel to one of the lateral surfaces (15, 16) of the closed volume (9).

15. The magnetic field sensor (1) of claim 13, wherein the fifth metal layer (26) electrically connects the first metal layer (10) to the second metal layer (11).

Images