Single light source atom magnetometer with low measurement dead zone and magnetic field measurement method

Abstract

The invention provides a single light source atom magnetometer with a low measurement dead zone and a magnetic field measurement method. The single light source atom magnetometer comprises a laser, an optical fiber splitter, a first collimator, a second collimator, an alkali metal atom gas chamber, an excitation magnetic field coil, a signal processor, a first photoelectric detector and a second photoelectric detector, according to the single-light-source atom magnetometer, the same light source is divided into two beams to detect the atom gas chamber at different angles, detection signals are obtained, the detection range of the atom magnetometer reaches 360 degrees, and the detection dead zone of the atom magnetometer is greatly reduced. By applying the technical scheme of the invention, the technical problem that the sensitivity is reduced or the measurement is failed when a magnetic field in a certain direction is measured due to the inherent measurement dead zone in the operation process of the traditional magnetometer is solved.

Description

Technical Field

[0001] This invention relates to the field of magnetic sensing technology, and in particular to a single-source atomic magnetometer with low measurement dead zone and a method for measuring magnetic fields. Background Technology

[0002] Atomic magnetometers, as one of the most sensitive magnetic sensing technologies currently available, have been widely applied in fields such as biomagnetic imaging, geological exploration, fundamental physics research, and non-destructive testing. However, traditional magnetometers have an inherent measurement blind zone during operation, leading to decreased sensitivity or measurement failure, forming a directional dead zone. This severely limits the application of atomic magnetometers in continuous, dynamic, and unsteady magnetic field measurement scenarios. Therefore, developing a high-precision atomic magnetometer with no or extremely low dead zone characteristics has urgent market demand and significant scientific value. Summary of the Invention

[0003] This invention provides a single-source atomic magnetometer with low measurement dead zone and a magnetic field measurement method, which can solve the technical problem that traditional magnetometers have an inherent measurement dead zone during operation, leading to decreased sensitivity or measurement failure and the formation of directional dead zone.

[0004] According to one aspect of the present invention, a single-source atomic magnetometer with low measurement dead zone is provided. The single-source atomic magnetometer with low measurement dead zone includes a laser, an optical fiber splitter, a first collimator, a second collimator, an alkali metal atomic gas cell, an excitation magnetic field coil, a signal processor, a first photodetector, and a second photodetector. The laser generates two laser beams through the optical fiber splitter. The first laser beam passes through the first collimator, and the second laser beam passes through the second collimator, and they are incident on the alkali metal atomic gas cell at an angle of 90°. The light signal emitted from the alkali metal atomic gas cell is converted into a first test signal and a second test signal containing atomic information by the first and second photodetectors. The signal processor generates an excitation magnetic field signal to achieve periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to coincide, the photodetector detects a decrease in light intensity. The lowest point of the test signal corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal according to the gyromagnetic ratio. The first and second test signals each yield a magnetic field signal, which is averaged to obtain the final output magnetic field signal.

[0005] Furthermore, the alkali metal atom gas cell is a square atom gas cell.

[0006] Furthermore, alkali metals include rubidium atoms.

[0007] According to another aspect of the present invention, a magnetic field measurement method with low measurement dead zone is provided, wherein the magnetic field measurement method with low measurement dead zone single-source atomic magnetometer as described above is used for magnetic field measurement.

[0008] Furthermore, the magnetic field measurement method with low measurement dead zone includes: a laser generates two laser beams through an optical fiber splitter; the first laser beam passes through a first collimator, and the second laser beam passes through a second collimator, and are incident on the alkali metal atom gas cell at an angle of 90°, one above the other. The light signal emitted from the alkali metal atom gas cell is converted into a first test signal and a second test signal containing atomic information by a first photodetector and a second photodetector; a signal processor generates an excitation magnetic field signal to achieve periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to be consistent, the photodetector detects a decrease in light intensity. The lowest point of the test signal corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal according to the gyromagnetic ratio. The first test signal and the second test signal each yield a magnetic field signal, which are averaged to obtain the final output magnetic field signal.

[0009] The present invention provides a single-source atomic magnetometer with low measurement dead zone. This single-source atomic magnetometer splits the same light source into two beams to probe the atomic gas cell at different angles, obtaining the detection signal. This allows the atomic magnetometer to achieve a 360° planar detection range, significantly reducing the detection dead zone. Therefore, compared with existing technologies, the single-source atomic magnetometer with low measurement dead zone provided by the present invention reduces the planar detection dead zone range of the magnetometer by using a single light source to vertically probe the atomic gas cell, achieving 360° dead-zone-free magnetic field detection with a single magnetometer. Attached Figure Description

[0010] The accompanying drawings, which form part of this specification, are provided to further illustrate embodiments of the invention and, together with the textual description, explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0011] Figure 1 A schematic diagram illustrating the working principle of a single-source atomic magnetometer with low measurement dead zone according to a specific embodiment of the present invention is shown.

[0012] Figure 2 A schematic diagram of the laser incident direction and position provided according to a specific embodiment of the present invention is shown.

[0013] The above figures include the following reference numerals:

[0014] 10. Laser; 20. Fiber optic splitter; 30. First collimator; 40. Second collimator; 50. Alkali metal atom gas cell; 60. Excitation magnetic field coil; 70. Signal processor; 80. First photodetector; 90. Second photodetector. Detailed Implementation

[0015] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0017] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0018] like Figure 1 and Figure 2As shown, a single-source atomic magnetometer with low measurement dead zone is provided according to a specific embodiment of the present invention. The single-source atomic magnetometer with low measurement dead zone includes a laser 10, an optical fiber splitter 20, a first collimator 30, a second collimator 40, an alkali metal atomic gas cell 50, an excitation magnetic field coil 60, a signal processor 70, a first photodetector 80, and a second photodetector 90. The laser 10 generates two laser beams through the optical fiber splitter 20. The first laser beam passes through the first collimator 30, and the second laser beam passes through the second collimator 40. They are incident on the alkali metal atomic gas cell 50 at an angle of 90°, one above the other. The light signal emitted from the alkali metal atomic gas cell 50 is converted into a first test signal and a second test signal containing atomic information by the first photodetector 80 and the second photodetector 90. The signal processor 70 generates an excitation magnetic field signal to realize periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to coincide, the photodetector detects a decrease in light intensity. The lowest point of the signal to be measured corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal based on the gyrometry ratio. The first and second signals to be measured each yield a magnetic field signal, which is then averaged to obtain the final output magnetic field signal.

[0019] This configuration provides a single-source atomic magnetometer with low measurement dead zone. This single-source atomic magnetometer splits the same light source into two beams to probe the atomic gas cell at different angles, obtaining the detection signal. This allows the atomic magnetometer to achieve a 360° planar detection range, significantly reducing the detection dead zone. Therefore, compared with existing technologies, the single-source atomic magnetometer with low measurement dead zone provided by this invention reduces the planar detection dead zone range of the magnetometer by using a single light source to vertically probe the atomic gas cell, achieving 360° dead-zone-free magnetic field detection with a single magnetometer.

[0020] In one specific embodiment of the present invention, the alkali metal atom gas chamber 50 is a square atom gas chamber. The alkali metal includes rubidium atoms.

[0021] According to another aspect of the present invention, a method for measuring magnetic fields with a low measurement dead zone is provided. This method uses a single-source atomic magnetometer with a low measurement dead zone as described above to measure the magnetic field. The method includes: a laser 10 generating two laser beams via an optical fiber splitter 20; a first laser beam passing through a first collimator 30 and a second laser beam passing through a second collimator 40; both beams entering an alkali metal atom gas cell 50 at an angle of 90°; and light signals emitted from the alkali metal atom gas cell 50 being converted into a first test signal and a second test signal containing atomic information by a first photodetector 80 and a second photodetector 90; and a signal processor 70 generating an excitation magnetic field signal to periodically scan the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to coincide, the photodetector detects a decrease in light intensity. The lowest point of the test signal corresponds to the excitation magnetic field frequency being the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal based on the gyromagnetic ratio. The first and second test signals each yield a magnetic field signal, which is then averaged to obtain the final output magnetic field signal.

[0022] This configuration provides a magnetic field measurement method with low measurement dead zone. This method uses a single-source atomic magnetometer with low measurement dead zone as described above. The single-source atomic magnetometer splits the same light source into two beams to probe the atomic gas cell at different angles, obtaining detection signals. This allows the atomic magnetometer to achieve a 360° plane detection range, significantly reducing the detection dead zone.

[0023] To gain a further understanding of the present invention, the following description is provided. Figure 1 and Figure 2 The present invention provides a detailed description of the single-source atomic magnetometer with low measurement dead zone provided by the present invention.

[0024] like Figure 1 and Figure 2 As shown, a specific embodiment of the present invention provides a single-source optically pumped atomic magnetometer with low measurement dead zone. This scheme utilizes a square atomic gas cell, splitting the same light source into two beams to detect signals at different angles, thereby enabling the atomic magnetometer to achieve a 360° planar detection range and significantly reducing the detection dead zone.

[0025] The working principle is as follows: Figure 1 As shown. The main body includes a laser, a rubidium atom gas chamber, an excitation magnetic field coil, a signal processor, and supporting optical components. A single laser is used with a 1-to-2 fiber optic splitter to generate two beams of light, as shown... Figure 2As shown, light enters the rubidium atom gas cell at a 90° angle from above and below. The light signal is converted into a test signal 1 and a test signal 2 containing atomic information by two photodetectors. The signal processor generates an excitation magnetic field signal to achieve periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to be consistent, the photodetector detects a decrease in light intensity. The lowest point of the test signal corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal according to the gyromagnetic ratio. The first test signal and the second test signal each yield a magnetic field signal, which are averaged to obtain the final output magnetic field signal.

[0026] This invention reduces the dead zone range of the magnetometer by using a single light source to vertically detect the atomic gas cell, thus enabling a single magnetometer to detect magnetic fields 360° without dead zones.

[0027] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0028] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A single-source atomic magnetometer with low measurement dead zone, characterized in that, The single-source atomic magnetometer with low measurement dead zone includes a laser (10), an optical fiber splitter (20), a first collimator (30), a second collimator (40), an alkali metal atom gas cell (50), an excitation magnetic field coil (60), a signal processor (70), a first photodetector (80), and a second photodetector (90). The laser (10) generates two laser beams through the optical fiber splitter (20). The first laser beam passes through the first collimator (30), and the second laser beam passes through the second collimator (40). They are incident on the alkali metal atom gas cell (50) at an angle of 90°. The light signal emitted from the alkali metal atom gas cell (50) is converted into a first test signal and a second test signal containing atomic information by the first photodetector (80) and the second photodetector (90). The signal processor (70) generates an excitation magnetic field signal to realize periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to coincide, the photodetector detects a decrease in light intensity. The lowest point of the signal to be measured corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal based on the gyrometry ratio. The first and second signals to be measured each yield a magnetic field signal, which is then averaged to obtain the final output magnetic field signal.

2. The single-source atomic magnetometer with low measurement dead zone according to claim 1, characterized in that, The alkali metal atom gas chamber (50) is a square atom gas chamber.

3. The single-source atomic magnetometer with low measurement dead zone according to claim 2, characterized in that, The alkali metal includes rubidium atoms.

4. A magnetic field measurement method with low measurement dead zone, characterized in that, The magnetic field measurement method with low measurement dead zone uses a single-source atomic magnetometer with low measurement dead zone as described in claims 1 to 3 to perform magnetic field measurement.

5. The magnetic field measurement method with low measurement dead zone according to claim 4, characterized in that, The magnetic field measurement method with low measurement dead zone includes: The laser (10) generates two laser beams through the fiber optic splitter (20). The first laser beam passes through the first collimator (30), and the second laser beam passes through the second collimator (40). They are incident on the alkali metal atom gas chamber (50) at an angle of 90°. The light signal emitted from the alkali metal atom gas chamber (50) is converted into a first test signal and a second test signal containing atomic information by the first photodetector (80) and the second photodetector (90). The signal processor (70) generates an excitation magnetic field signal to achieve periodic scanning of the magnetic field frequency. During the excitation magnetic field scanning, when the excitation magnetic field frequency and the external magnetic field frequency tend to be consistent, the photodetector detects a decrease in light intensity. The lowest point of the signal to be measured corresponds to the excitation magnetic field frequency, which is the external magnetic field frequency. The magnetic field frequency is converted into a magnetic field signal according to the gyromagnetic ratio. The first and second signals to be measured each obtain a magnetic field signal, and the average of these signals is the final output magnetic field signal.

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