JP-7854610-B2 - Magnetic field measuring device

JP7854610B2JP 7854610 B2JP7854610 B2JP 7854610B2JP-7854610-B2

Inventors

芳井義治
浜田真吾
佐光暁史
竹村祐輝
水落憲和

Assignees

スミダコーポレーション株式会社
国立大学法人京都大学

Dates

Publication Date: 20260507
Application Date: 20221013

Claims (9)

A magnetic resonance component capable of quantum manipulation of electron spins using microwaves, A high-frequency magnetic field generator that applies the microwave to the magnetic resonance member, A magnet that applies a static magnetic field to the magnetic resonance member, An irradiation device that irradiates the magnetic resonance member with incident light of a specific wavelength, A flux transformer that senses the magnetic field to be measured with a primary coil and applies an applied magnetic field corresponding to the sensed magnetic field to be measured to the magnetic resonance member with a secondary coil, A columnar first light guide member that guides the incident light to the magnetic resonance member, The system comprises a columnar second light guide member that guides the fluorescence emitted by the magnetic resonance member away from the magnetic resonance member, The magnetic resonance member is positioned between the end face of the first light guide member and the end face of the second light guide member in the hollow portion of the secondary coil of the flux transformer and the hollow portion of the magnet. The secondary coil is a bobbinless coil. A magnetic field measuring device characterized by the following.
The aforementioned high-frequency magnetic field generator includes a substantially circular and plate-shaped coil section that emits microwaves, The coil section has two openings, The first light guide member is positioned to penetrate one of the two openings, The second light guide member is positioned to penetrate the other of the two openings. A magnetic field measuring device according to claim 1, characterized by the following:
The aforementioned high-frequency magnetic field generator comprises two substantially circular coil sections that emit microwaves, At least a portion of the first light guide member and at least a portion of the second light guide member are arranged in the space between the two coil portions. A magnetic field measuring device according to claim 1, characterized by the following:
The substrate further comprises a wiring pattern that conducts the aforementioned high-frequency microwave current, A first plate-shaped member and, A second plate-shaped member is arranged substantially parallel to the first plate-shaped member, The first coil portion of the two coil portions is arranged on the surface of the first plate-shaped member. The second coil portion of the two coil portions is positioned on the surface of the second plate-shaped member facing the surface of the first plate-shaped member. The high-frequency magnetic field generator further comprises a first terminal portion extending from the first coil portion along the side surface of the first plate-shaped member, and a second terminal portion extending from the second coil portion along the side surface of the second plate-shaped member. The first plate-shaped member and the second plate-shaped member are each arranged upright on the substrate, The first terminal portion and the second terminal portion are electrically connected to the wiring pattern of the substrate. A magnetic field measuring device according to claim 3, characterized by the following:
The magnetic field measuring device according to claim 4, further comprising a filling member formed by filling the space between the first plate-shaped member and the second plate-shaped member with a cured resin.
The magnetic field measuring device according to claim 5, characterized in that the filling member is provided with an observation hole for optically observing the magnetic resonance member from the opposite side of the substrate.
The magnetic field measuring device according to any one of claims 1 to 6, further comprising an optical member disposed adjacent to the end face of the first light guide member, which transmits excitation light as incident light and reflects fluorescence.
The magnetic field measuring device according to any one of claims 1 to 6, characterized in that the secondary coil is wound around at least one of the first light guide member, the second light guide member, and the magnetic resonance member.
The magnetic field measuring device according to any one of claims 1 to 6, characterized in that the secondary coil comprises a copper wire and a transparent coating.

Description

This invention relates to a magnetic field measuring device. One magnetic field measuring device performs magnetic measurements using optically detected magnetic resonance (ODMR), which utilizes the electron spin resonance of sensing elements such as diamond structures containing nitrogen and lattice defects (NV centers) (see, for example, Patent Document 1). In ODMR, a static magnetic field is applied to the magnetic resonance element, such as diamond containing NV centers, separately from the magnetic field being measured. Laser light (excitation light and measurement light) and microwaves are applied in a predetermined sequence, and the amount of fluorescence emitted from the magnetic resonance element is detected. Based on this amount of light, the magnetic flux density of the magnetic field being measured is derived. For example, in the Ramsay pulse sequence, (a) excitation light is irradiated onto the NV center, (b) a first π/2 pulse of microwaves is applied to the NV center, (c) a second π/2 pulse of microwaves is applied to the NV center at a predetermined time interval tt from the first π/2 pulse, (d) measurement light is irradiated onto the NV center to measure the amount of light emitted from the NV center, and (e) the magnetic flux density is derived based on the measured amount of light emitted. Furthermore, in the spin echo pulse sequence, (a) excitation light is irradiated onto the NV center, (b) a first π/2 microwave pulse is applied to the NV center at a phase of 0 degrees of the magnetic field under measurement, (c) a π microwave pulse is applied to the NV center at a phase of 180 degrees of the magnetic field under measurement, (d) a second π/2 microwave pulse is applied to the NV center at a phase of 360 degrees of the magnetic field under measurement, (e) measurement light is irradiated onto the NV center to measure the amount of light emitted from the NV center, and (f) the magnetic flux density is derived based on the measured amount of light emitted. Furthermore, some magnetic sensors include a superconducting quantum interferometer (SQUID: Superconducting Quantum Interference Device) and a flux transformer that detects the magnetic field to be measured with a pickup coil and applies it to the SQUID with an input coil (see, for example, Patent Document 2). Japanese Patent Publication No. 2020-8298Japanese Patent Application Publication No. 8-75834 Figure 1 is a block diagram showing the configuration of a magnetic field measuring device according to an embodiment of the present invention.Figure 2 is a cross-sectional view showing the primary coil of the transformer in Figure 1.Figure 3 illustrates the arrangement of the primary coil of the transformer during magnetic field measurement.Figure 4 is a perspective view showing an example of the configuration of a part of the magnetic sensor section shown in Figure 1.Figure 5 is a side view showing an example of the optical system configuration in the magnetic sensor section shown in Figure 1.Figure 6 is a perspective view (1/3) showing a modified example of the magnetic sensor section (partially) shown in Figure 1.Figure 7 is a perspective view (2/3) showing a modified example of the magnetic sensor section (partially) shown in Figure 1.Figure 8 is a perspective view showing a modified example of the magnetic sensor section (partially) shown in Figure 1 (3/3).Figure 9 is a cross-sectional view showing an example of a light guide member and a magnetic resonance member in a magnetic field measuring device according to Embodiment 2.Figure 10 is a perspective view (1/3) showing an example of a high-frequency magnetic field generator in Embodiment 3.Figure 11 is a perspective view showing an example of a high-frequency magnetic field generator in Embodiment 3 (2/3).Figure 12 is a perspective view showing an example of a high-frequency magnetic field generator in Embodiment 3 (3/3).Figure 13 is a perspective view (1/2) showing an example of a light guide member, a magnetic resonance member, and a secondary coil of a flux transformer in a magnetic field measuring device according to Embodiment 4.Figure 14 is a perspective view showing an example of a light guide member, a magnetic resonance member, and a secondary coil of a flux transformer in a magnetic field measuring device according to Embodiment 4 (2/2).Figure 15 is a perspective view showing the configuration of a part of the magnetic sensor section in the magnetic field measuring device according to Embodiment 5.Figure 16 is a perspective view (1/2) showing an example of the secondary coil of a flux transformer in Embodiment 6.Figure 17 is a perspective view showing an example of the secondary coil of a flux transformer in Embodiment 6 (2/2).Figure 18 is a perspective view showing the configuration of a part of the magnetic sensor section in the magnetic field measuring device according to Embodiment 7.Figure 19 is a perspective view (1/2) showing the configuration of a part of the magne