Physical package for optical lattice clock
A physical package is provided with: a MOT device; an optical chamber which constitutes an optical lattice formation portion; and a vacuum chamber which surrounds these components and has a substantially cylindrical shape. The MOT device is arranged along the beam axis of an atomic beam and traps an atom cluster. The optical lattice formation portion uses optical lattice light that enters therein to form an optical lattice in a cavity, confines the atom cluster trapped by the MOT device in the optical lattice, and transfers, along the X-axis which is a movement axis perpendicular to the beam axis, the atom cluster to a clock transition space which facilitates clock transition. The central axis of the cylinder of the main body of the vacuum chamber passes through the clock transition space, and is set to be substantially parallel with the beam axis.
1 . A physics package for an optical lattice clock, the physics package comprising:
a Magneto-Optical Trap (MOT) device that is arranged along a beam axis of an atom beam, and captures an atom population;
an optical lattice formation portion that forms an optical lattice using incident optical lattice light, confines the atom population captured by the MOT device in the optical lattice, and moves the atom population to a clock transition space for prompting clock transition along a movement axis perpendicular to the beam axis; and
a vacuum chamber that comprises a cylindrical-shaped or prism-shaped main body that encloses the MOT device and the optical lattice formation portion,
wherein a central axis of the vacuum chamber passes through the clock transition space, and is configured parallel with the beam axis, being spaced apart from the beam axis by a finite, non-zero distance,
wherein the vacuum chamber comprises a protruding portion that protrudes from the main body along the beam axis, and
the physics package further comprises a slower that decelerates the atom population, on an upstream side of the MOT device on the beam axis, and
the slower is arranged astride the main body and the protruding portion, and
the slower comprises magnetic coils.
2 . The physics package for the optical lattice clock according to claim 1 ,
wherein in the MOT device, MOT light is emitted in both directions of each of three axes that comprise the beam axis and two axes that are perpendicular to the beam axis and are different from the movement axis.
3 . The physics package for the optical lattice clock according to claim 2 ,
wherein at the slower,
deceleration light is emitted upstream along the beam axis, and
the main body comprises: a pair of first vacuum-resistant optical windows that allow passage of the MOT light and the deceleration light along the beam axis; and a pair of second vacuum-resistant optical windows that allow passage of the MOT light along the two axes.
4 . The physics package for the optical lattice clock according to claim 1 , further comprising
a vacuum pump cartridge that vacuumizes the vacuum chamber,
wherein the vacuum pump cartridge is arranged in the main body so as to be lined up with the slower but is decentered in a direction different from a direction of the slower.
5 . The physics package for the optical lattice clock according to claim 1 ,
wherein the cylindrical-shaped or prism-shaped main body is formed to have a quadrilateral prism shape, a hexagonal prism shape, a octagonal prism shape, or a cylindrical shape.