Microwave antenna of large-bandwidth NV color center quantum sensor and quantum sensor

Abstract

The invention relates to the technical field of microwave antennas, in particular to a microwave antenna of a large-bandwidth NV color center quantum sensor and the quantum sensor. The antenna structure comprises a feed port, a load port, a feed structure and a radiation structure. Wherein the feed port is used for accessing a microwave signal; the load port is used for connecting load equipment; the feed structure is connected with the feed port and is used for accessing and transmitting the microwave signal, and the feed structure is also connected with the load port; the radiation structure is connected with the feed structure and is used for receiving the microwave signal transmitted by the feed structure and converting the microwave signal into a radiation microwave field; the radiation structure comprises a microstrip line and an open-circuit branch, and the open-circuit branch is formed by tapping one end of the microstrip line. The antenna structure can improve the uniformity of a radiation field.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microwave antennas, in particular to a microwave antenna of a large-bandwidth NV color center quantum sensor and a quantum sensor. BACKGROUND

[0002] With the rapid development of quantum technology, quantum sensors, as an important branch, have shown great potential in basic scientific research and industrial application fields due to their ultra-high sensitivity, high spatial resolution and the characteristics of working at normal temperature and pressure. Among them, the quantum sensor based on nitrogen-vacancy (NV) color center has become one of the research hotspots in the current quantum sensing field due to its unique quantum properties and relatively friendly operating environment. The NV color center is a point defect in a diamond crystal, which is formed by a nitrogen atom replacing a carbon atom and combining with an adjacent vacancy. Its electron spin has a ground-state spin triplet that can be optically initialized and read out. Under the action of external magnetic field, electric field, temperature and other physical fields, its energy level will be split or moved, and then the changes of fluorescence intensity or spin relaxation time reflect the changes of external physical quantities. This characteristic makes the NV color center an ideal quantum sensing platform, which can be used to detect magnetic field, electric field, temperature and pressure and other physical quantities. Quantum sensors are devices that use quantum states or quantum coherence to measure physical quantities. Compared with traditional sensors, quantum sensors can theoretically achieve the measurement precision of the Heisenberg limit, far exceeding the performance limit of classical sensors.

[0003] In related technologies, the NV color center quantum sensing system is usually composed of a diamond NV color center platform, an optical excitation and collection module, a microwave excitation module and a signal processing unit. Among them, the microwave excitation module is used to manipulate the spin state of the NV color center, and the core component is a microwave antenna. The function of the microwave antenna is to generate a high-frequency electromagnetic field to drive the electron spin energy level transition of the NV color center in a resonant manner, so as to realize the coherent control of the spin state. Common types of microwave antennas include coplanar waveguide (CPW), microstrip line or loop antenna, etc. These antennas are usually fabricated on the surface of the diamond or the substrate by photolithography process, and their performance directly affects the uniformity, intensity and spatial resolution of the microwave field.

[0004] However, the microwave antenna of the current NV color center quantum sensor has the following technical problems:

[0005] The structure of the existing microwave antenna has defects in uniformity and needs to be optimized. SUMMARY

[0006] Therefore, it is necessary to provide a microwave antenna and a quantum sensor for a large bandwidth NV color center quantum sensor that can increase the area of ​​the radiated microwave field and enhance the radiation intensity.

[0007] This application provides a microwave antenna for a high-bandwidth NV color center quantum sensor, characterized in that it comprises:

[0008] The power supply port is used to receive microwave signals;

[0009] Load port, used to connect load devices;

[0010] A power supply structure is connected to the power supply port for receiving and transmitting the microwave signal; the power supply structure is also connected to the load port.

[0011] A radiating structure, connected to the feeding structure, is used to receive the microwave signal transmitted by the feeding structure and convert the microwave signal into a radiated microwave field;

[0012] The radiating structure includes a microstrip line and an open-circuit stub, wherein the open-circuit stub is formed by tapping one end of the microstrip line.

[0013] In one embodiment, the open-circuit spur is a spiral spur.

[0014] In one embodiment, the helical direction of the open-circuit stub is configured according to the performance requirements of the microwave antenna.

[0015] In one embodiment, the length of the open-circuit stub is less than one-quarter of the wavelength of the highest operating frequency of the microwave antenna.

[0016] In one embodiment, the open-circuit spur is a planar spiral structure, and the open-circuit spur is printed on a PCB substrate.

[0017] In one embodiment, the open-circuit spur is a three-dimensional spiral structure.

[0018] In one embodiment, the microstrip line is a semi-enclosed structure, and the radiating structure is located in the area enclosed by the semi-enclosed structure of the microstrip line. The microwave antenna also includes a reference ground structure, which is located in a different structural layer than the radiating structure. The reference ground structure has an opening corresponding to the area where the radiating structure is located.

[0019] In one embodiment, the performance parameters of the radiating structure are adjusted by regulating at least one of the following structural parameters:

[0020] The dimensions of the power supply structure;

[0021] The line width, length or winding spacing of the open-circuit stub;

[0022] The relative position of the open-circuit stub and the short-circuit stub.

[0023] In one of the embodiments, the connection positions of the feed port and the load port are compatible with each other.

[0024] In a second aspect, the application further provides a quantum sensor comprising the microwave antenna of the large-bandwidth NV center quantum sensor according to any one of the first aspect.

[0025] The microwave antenna of the large-bandwidth NV center quantum sensor and the quantum sensor described above can achieve the following beneficial effects in solving the technical problems proposed in the corresponding background art through the technical features in the claims:

[0026] The application provides a microwave antenna of a large-bandwidth NV center quantum sensor, which comprises a feed port, a load port, a feed structure and a radiation structure. The feed port is used to access a microwave signal; the load port is used to connect a load device; the feed structure is connected with the feed port and is used to access and transmit the microwave signal, and the feed structure is also connected with the load port; the radiation structure is connected with the feed structure and is used to receive the microwave signal transmitted by the feed structure and convert the microwave signal into a radiation microwave field; the radiation structure comprises a microstrip line and an open-circuit stub, and the open-circuit stub is formed by tapping one end of the microstrip line. In the implementation, the radiation structure helps to form a symmetrically extended current path by setting the open-circuit stub, thereby generating a plurality of radiation sources with controllable phase and direction, so that the radiation microwave field can form superposition in a specified area to form a uniform field. The current at the end of the open-circuit stub is zero and the voltage is maximum, thereby forming a current antinode point, which helps to further shape the uniform radiation microwave field and avoids the situation that a single radiation source can only produce a field distribution with strong center and weak edges, and ultimately helps to produce a large-area, high-intensity and uniform radiation microwave field. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0028] Figure 1 FIG. 1 is a structural schematic diagram of a microwave antenna of a large-bandwidth NV center quantum sensor in an embodiment of the application;

[0029] Figure 2This is a partial structural diagram of the radiation structure in an embodiment of this application;

[0030] Figure 3 This is a schematic diagram of the reference ground structure in an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures: 100, radial structure; 101, microstrip line; 102, open-circuit stub; 200, feed structure; 300, feed port; 400, load port; 500, reference ground structure. Detailed Implementation

[0032] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0034] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0035] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0036] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0037] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0038] This application was made by the inventor based on his understanding and research into the following issues:

[0039] In related technologies, NV center quantum sensing systems typically consist of a diamond NV center platform, an optical excitation and collection module, a microwave excitation module, and a signal processing unit. The microwave excitation module is used to manipulate the spin states of the NV centers, and its core component is a microwave antenna. The microwave antenna generates a high-frequency electromagnetic field to resonately drive the electron spin level transitions of the NV centers, thereby achieving coherent control of the spin states. Commonly used microwave antenna types include coplanar waveguides (CPWs), microstrip lines, or loop antennas. These antennas are usually fabricated on diamond surfaces or substrates using photolithography, and their performance directly affects the uniformity, intensity, and spatial resolution of the microwave field.

[0040] However, the microwave antennas of current NV color center quantum sensors have the following technical problems:

[0041] The existing structure of microwave antennas has defects in uniformity and needs to be optimized.

[0042] Based on the above problems, this application provides a microwave antenna for a high-bandwidth NV color center quantum sensor and a quantum sensor.

[0043] In one embodiment, it can be as follows Figure 1 and Figure 2 As shown in the embodiment of this application, a microwave antenna for a high-bandwidth NV color center quantum sensor may include a feed port 300, a load port 400, a feed structure 200, and a radiation structure 100.

[0044] The power supply port 300 is used to receive microwave signals.

[0045] Among them, load port 400 is used to connect load devices.

[0046] The power supply structure 200 is connected to the power supply port 300 for receiving and transmitting the microwave signal, and the power supply structure 200 is also connected to the load port 400.

[0047] The radiating structure 100 is connected to the feeding structure 200 and is used to receive the microwave signal transmitted by the feeding structure 200 and convert the microwave signal into a radiated microwave field. The radiating structure 100 includes a microstrip line 101 and an open-circuit stub 102, wherein the open-circuit stub 102 is formed by tapping one end of the microstrip line 101.

[0048] By implementing the microwave antenna for a high-bandwidth NV color center quantum sensor as described above, the following beneficial effects can be achieved:

[0049] This application provides a microwave antenna for a high-bandwidth NV color center quantum sensor, including a feed port 300, a load port 400, a feed structure 200, and a radiating structure 100. The feed port 300 is used to receive microwave signals; the load port 400 is used to connect a load device; the feed structure 200 is connected to the feed port 300 and is used to receive and transmit the microwave signals, and is also connected to the load port 400; the radiating structure 100 is connected to the feed structure 200 and is used to receive the microwave signals transmitted by the feed structure 200 and convert the microwave signals into a radiated microwave field; the radiating structure 100 includes a microstrip line 101 and an open-circuit stub 102, the open-circuit stub 102 being formed by tapping one end of the microstrip line 101. In implementation, by setting the open-circuit stub 102, the radiating structure 100 helps to form symmetrically extended current paths, thereby generating multiple phased and directionally controllable radiation sources, allowing the radiated microwave fields to superimpose within a specified region to form a uniform field. Among them, the current at the end of the open-circuit stub 102 is zero and the voltage is maximum, thus forming a current antinode. This helps to further shape a uniform radiated microwave field, avoiding the situation where a single radiation source can only produce a field distribution that is strong in the center and weak at the edges. Ultimately, this helps to generate a large-area, high-intensity and uniform radiated microwave field.

[0050] In one embodiment, it can be as follows Figure 2 As shown, the open-circuit support 102 is a spiral support.

[0051] In this embodiment, by setting a spiral branch, it is helpful to extend the current path in a limited space, which exceeds the extension performance of a simple straight line. Furthermore, due to the symmetry of the spiral, the generated magnetic field vectors can be superimposed in the same direction, which helps to enhance the radiated microwave field.

[0052] In one embodiment, the helical direction of the open-circuit stub 102 is configured according to the performance requirements of the microwave antenna.

[0053] In this embodiment, by setting the spiral direction to match performance requirements, it is helpful to configure the distribution of the electromagnetic field according to the actual usage requirements, which helps to improve the flexibility of microwave antenna configuration.

[0054] In one embodiment, the length of the open-circuit stub 102 is less than one-quarter of the wavelength of the highest operating frequency of the microwave antenna.

[0055] In this embodiment, by limiting the length of the open-circuit stub 102 to a specific wavelength fraction below the highest operating frequency, it helps to ensure that the open-circuit stub 102 does not undergo harmful resonance throughout the target frequency band and can effectively radiate energy, thereby enhancing the performance of the microwave antenna.

[0056] In one embodiment, the open-circuit spur 102 is a planar spiral structure, and the open-circuit spur 102 is printed on a PCB substrate.

[0057] In this embodiment, by setting a planar spiral structure, it is helpful to build a quantum sensor in a compact space, thus saving space.

[0058] In one embodiment, the open-circuit spur 102 is a three-dimensional spiral structure.

[0059] In this embodiment, by setting a three-dimensional spiral structure, it is possible to set the field strength and radiation mode more flexibly, thereby improving the flexibility of quantum sensor configuration.

[0060] In one embodiment, the microstrip line 101 is a semi-enclosed structure, and the radiating structure 100 is disposed in the region enclosed by the semi-enclosed structure of the microstrip line 101. The microwave antenna also includes a reference ground structure 500, which is disposed in a different structural layer from the radiating structure 100. The reference ground structure 500 has openings corresponding to the region where the radiating structure 100 is located.

[0061] In this embodiment, by setting a semi-enclosed microstrip line 101 structure, it is helpful to better confine microwave energy within the target area (i.e., within the enclosed area), further optimizing the uniformity and intensity of the microwave field above the radiating structure 100. Setting an opening on the reference ground structure 500 helps to reduce the effect of the reference ground plane eddy current on the radiated microwave field, which helps to further optimize the performance of the microwave antenna.

[0062] In one embodiment, the performance parameters of the radiation structure 100 are adjusted by regulating at least one of the following structural parameters:

[0063] The dimensions of the power supply structure 200;

[0064] The line width, length, or winding spacing of the open-circuit branch 102;

[0065] The relative positions of the open-circuit branch 102 and the short-circuit branch.

[0066] In this embodiment, adjusting the performance parameters of the radiating structure 100 through structural parameters helps to configure the performance of the radiating structure 100 according to requirements, thereby improving the flexibility of microwave antenna applications.

[0067] In one embodiment, the connection positions of the power supply port 300 and the load port 400 are compatible.

[0068] In this embodiment, during system integration, the input port can be freely selected based on the convenience of PCB wiring, which helps to improve the flexibility of microwave antenna configuration.

[0069] Based on the same inventive concept, this application also provides a quantum sensor, including a microwave antenna for a high-bandwidth NV color center quantum sensor according to any one of the above embodiments.

[0070] It is understood that the microwave antenna and quantum sensor of the aforementioned high-bandwidth NV color center quantum sensor can also take other forms, not limited to those mentioned in the above embodiments, as long as they can achieve the function of improving the uniformity of the radiated microwave field.

[0071] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A microwave antenna for a high-bandwidth NV color center quantum sensor, characterized in that, include: The power supply port is used to receive microwave signals; Load port, used to connect load devices; Power supply structure; The power supply structure is connected to the power supply port for receiving and transmitting the microwave signal, and is also connected to the load port. A radiating structure, connected to the feeding structure, is used to receive the microwave signal transmitted by the feeding structure and convert the microwave signal into a radiated microwave field; The radiating structure includes a microstrip line and an open-circuit stub, wherein the open-circuit stub is formed by tapping one end of the microstrip line.

2. The microwave antenna for a high-bandwidth NV color center quantum sensor according to claim 1, characterized in that, The open-circuit branch is a spiral branch.

3. The microwave antenna for a high-bandwidth NV color center quantum sensor according to claim 2, characterized in that, The spiral direction of the open-circuit stub is configured according to the performance requirements of the microwave antenna.

4. The microwave antenna for a large bandwidth NV color center quantum sensor according to claim 2, characterized in that, Its features are, The length of the open-circuit stub is less than one-quarter of the wavelength of the highest operating frequency of the microwave antenna.

5. The microwave antenna for a high-bandwidth NV color center quantum sensor according to claim 1, characterized in that, The open-circuit support is a planar spiral structure, and the open-circuit support is printed on a PCB substrate.

6. A microwave antenna for a large bandwidth NV color center quantum sensor according to any one of claims 1 to 5, characterized in that, The open-circuit support has a three-dimensional spiral structure.

7. The microwave antenna for a high-bandwidth NV color center quantum sensor according to claim 1, characterized in that, The microstrip line has a semi-enclosed structure, and the radiating structure is located in the area enclosed by the semi-enclosed structure of the microstrip line. The microwave antenna also includes a reference ground structure, which is located in a different structural layer than the radiating structure. The reference ground structure has an opening corresponding to the area where the radiating structure is located.

8. The microwave antenna for a large bandwidth NV color center quantum sensor according to claim 7, characterized in that, The performance parameters of the radiation structure are adjusted by adjusting at least one of the following structural parameters: The dimensions of the power supply structure; The line width, length, or winding spacing of the open-circuit branch; The relative positions of the open-circuit branch and the short-circuit branch.

9. The microwave antenna for a high-bandwidth NV color center quantum sensor according to claim 1, characterized in that, The connection positions of the power supply port and the load port are compatible.

10. A quantum sensor, characterized in that, The microwave antenna includes a high-bandwidth NV color center quantum sensor according to any one of claims 1-9.

Images