Triaxial magnetic field correction coil, physics package, physics package for optical lattice clock, physics package for atomic clock, physics package for atom interferometer, physics package for quantum information processing device, and physics package system

Patent metadata

Field	Value
Publication number	US-11929754-B2
Application number	US-202117915720-A
Country	US
Kind code	B2
Filing date	Mar 30, 2021
Priority date	Mar 31, 2020
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

There is a need to maintain or enhance the magnetic field correction accuracy of a physics package while making the physics package more compact and portable. A triaxial magnetic field correction coil is provided inside a vacuum chamber surrounding a clock transition space having atoms disposed therein. The triaxial magnetic field correction coil is formed into a shape such that it is possible to correct, for magnetic field components of three axial directions passing through the clock transition space, a constant term, a first order spatial derivative term, a second order spatial derivative term, a third or higher order spatial derivative term, or some given combination of these terms. The triaxial magnetic field correction coil can be used in, for example, a physics package for an optical lattice clock.

First claim

The invention claimed is:

1. A physics package, comprising:
a triaxial magnetic field correction coil comprising a shape configured to correct any of a constant term, a first order spatial derivative term, a second order spatial derivative term, and a three or higher order spatial derivative term, or any combination of the terms; and
a vacuum chamber that encloses a clock transition space in which atoms are arranged.

2. The physics package according to claim 1 ,
wherein the vacuum chamber comprises an inner wall formed to have a point-symmetric shape centered in the clock transition space in a first axis among the three axes, and
the triaxial magnetic field correction coil comprises a group of coils that is formed to have a point-symmetric shape centered in the clock transition space in a direction of the first axis, and is arranged on the inner wall or adjacent to the inner wall.

3. The physics package according to claim 2 ,
wherein the triaxial magnetic field correction coil comprises two or more groups of coils that have different coil sizes, coil shapes, or distances in the first axis.

4. The physics package according to claim 2 , further comprising
a holder that has a sparse structure and is detachably attached around the inner wall of the vacuum chamber,
wherein the group of coils is attached to the holder.

5. The physics package according to claim 2 ,
wherein the vacuum chamber is formed to have a point-symmetric shape centered in the clock transition space in a second axis that is an axis other than the first axis among the three axes, and
the triaxial magnetic field correction coil comprises a group of coils that is formed to have a point-symmetric shape centered in the clock transition space in a direction of the second axis, and is arranged on the inner wall or adjacent to the inner wall.

6. The physics package according to claim 5 ,
wherein the vacuum chamber is formed to have a point-symmetric shape centered in the clock transition space in a third axis that is an axis other than the first axis and the second axis among the three axes, and
the triaxial magnetic field correction coil comprises a group of coils that is formed to have a point-symmetric shape centered in the clock transition space in a direction of the third axis, and is arranged on the inner wall or adjacent to the inner wall.

7. The physics package according to claim 2 ,
wherein the vacuum chamber is formed to have a substantially cylindrical shape allowing the clock transition space to be disposed on a central axis of the cylinder.

8. The physics package according to claim 2 ,
wherein the vacuum chamber is formed to have a substantially spherical shape allowing the clock transition space to be disposed at a center of the sphere.

9. The physics package according to claim 2 ,
wherein at least a pair of walls of the vacuum chamber that face each other have substantially square shapes, and the clock transition space is formed to have a substantially rectangular shape arranged on an axis connecting centers of the pair of walls.

10. The physics package according to claim 2 ,
wherein at least part of the group of coils are formed on a flexible printed board, and are attached to the inner wall formed to have the point-symmetric shape or to a holder formed to have a point-symmetric shape around the inner wall.

11. The physics package according to claim 1 ,
further comprising:
a pair of MOT coils that are provided in the vacuum chamber, form a gradient magnetic field, and capture atoms in a capture space of the MOT device;
a bias coil that is provided in the vacuum chamber, and is for generating a bias magnetic field at a position where the atoms are captured; and
movement means for moving the atoms captured in the capture space to the clock transition space by a moving optical lattice,
wherein at least part of the triaxial magnetic field correction coil is supported by a supporter that supports the MOT coils.

12. The physics package according to claim 1 ,
wherein an optical resonator that comprises an optical mirror that forms an optical lattice is provided around the clock transition space in the vacuum chamber, and
at least part of the triaxial magnetic field correction coil is provided in the optical resonator.

13. The physics package according to claim 1 ,
wherein at least part of the triaxial magnetic field correction coil are provided around an inner wall of the vacuum chamber.

14. A physics package system, comprising:
the physics package according to claim 2 ; and
a control device that controls current that flows to the triaxial magnetic field correction coil.

15. The physics package according to claim 1 ,
wherein the physics package is for an optical lattice clock.

16. The physics package according to claim 1 ,
wherein the physics package is for an atomic clock.

17. The physics package according to claim 1 ,
wherein the physics package is for an atom interferometer.

18. The physics package according to claim 1 ,
wherein the physics package is for a quantum information processing device for atoms or ionized atoms.

19. The physics package according to claim 1 , further comprising
at least one atomic laser cooling technology device among a Zeeman slower, a magneto-optical trap, and an optical lattice trap that guide the atoms into the clock transition space.

Assignees

• Jeol Ltd
• Riken

Inventors

• Tsuji Shigenori
• Takamoto Masao
• Katori Hidetoshi

Classifications

• H03L7/26 Primary

  using energy levels of molecules, atoms, or subatomic particles as a frequency reference · CPC title

• G04F5/145

  using Coherent Population Trapping · CPC title

• H01F7/20

  without armatures (cores H01F3/00; coils H01F5/00 {; shaping metal by applying magnetic forces B21D26/14; electromagnets specially adapted for NMR applications G01R33/381}) · CPC title

• G04F5/14 Primary

  using atomic clocks · CPC title

• G01V7/14

  using free-fall time · CPC title