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 provided inside a vacuum chamber surrounding a clock transition space having atoms disposed therein. The triaxial magnetic field correction coil 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.

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 provided inside a vacuum chamber surrounding a clock transition space having atoms disposed therein. The triaxial magnetic field correction coil 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.

A reference time generator including a first clock source including a reference synthesizer and cesium atomic clock configured to produce a cesium reference signal and a cesium QOT metric, a second clock source including a reference synthesizer and rubidium atomic clock configured to produce a rubidium reference signal and a rubidium QOT metric, and a circuit for selecting from the clock sources one reference signal based on the best QOT metric.

The invention discloses a physical system of strontium optical clock applied for space station, relating to the field of optical atomic clocks, comprising a special-shaped cavity and a MOT cavity. A Zeeman slower is arranged between the special-shaped cavity and the MOT cavity, and the special-shaped cavity and the MOT cavity are provided with a plurality of interfaces that communicate with their interiors; an internal heating atomic oven is arranged in the special-shaped cavity, and an anti-Helmholtz coil and a remanence compensation coil are arranged on the outer wall of the MOT cavity; the two cavities are both connected with a vacuum device for forming a vacuum, and both the special-shaped cavity and the MOT cavity are provided with optomechanical components. The system integrates the internal heating atomic oven in the special-shaped cavity to reduce the space occupied by the heating atomic oven.

The invention discloses a physical system of strontium optical clock applied for space station, relating to the field of optical atomic clocks, comprising a special-shaped cavity and a MOT cavity. A Zeeman slower is arranged between the special-shaped cavity and the MOT cavity, and the special-shaped cavity and the MOT cavity are provided with a plurality of interfaces that communicate with their interiors; an internal heating atomic oven is arranged in the special-shaped cavity, and an anti-Helmholtz coil and a remanence compensation coil are arranged on the outer wall of the MOT cavity; the two cavities are both connected with a vacuum device for forming a vacuum, and both the special-shaped cavity and the MOT cavity are provided with optomechanical components. The system integrates the internal heating atomic oven in the special-shaped cavity to reduce the space occupied by the heating atomic oven.

A modular programmable software defined atomic clock system includes an oscillator configured to output a periodic, oscillating electrical signal, an atomic clock physics package system, and a programmable logic controller. The atomic clock physics package system is configured to generate a reference signal based on detected electron spin transitions between two hyperfine energy levels in atoms stored in the atomic clock physics package system. The programmable logic controller is coupled to the oscillator and the atomic clock physics package system. The programmable logic controller is configured to: detect an error signal based on the generated reference signal and the periodic, oscillating electrical signal; adjust the periodic, oscillating electrical signal based on the detected error signal; and generate and output one or more output signals in one or more frequencies from the adjusted periodic, oscillating electrical signal.

A millimeter wave apparatus, with a substrate, a transceiver in a first fixed position relative to the substrate, and a gas cell in a second fixed position relative to the substrate. The clock apparatus also comprises at least four waveguides.

A millimeter wave apparatus, with a substrate, a transceiver in a first fixed position relative to the substrate, and a gas cell in a second fixed position relative to the substrate. The clock apparatus also comprises at least four waveguides.

A miniature atomic clock with pulse mode operation. The clock includes: a local oscillator; a dual-frequency laser source; a pulsing element to pulse the output signal from the source according to a Ramsey-type interrogation sequence having pulses with duration T1 separated by intervals with duration T2; an alkaline vapour microcell; a photodiode; a feedback control loop for controlling the microwave frequency of the local oscillator; and a feedback control loop for controlling the optical frequency of the source by using a pulse control block receiving the output signal from the photodiode and the interrogation sequence, and providing a correction signal to the source. During the period T1, the block extracts an error signal from the output signal received from the photodiode and generates the correction signal from the error signal. During the period T2, the block resets the error signal to zero and generates the correction signal by extrapolation.

A miniature atomic clock with pulse mode operation. The clock includes: a local oscillator; a dual-frequency laser source; a pulsing element to pulse the output signal from the source according to a Ramsey-type interrogation sequence having pulses with duration T1 separated by intervals with duration T2; an alkaline vapour microcell; a photodiode; a feedback control loop for controlling the microwave frequency of the local oscillator; and a feedback control loop for controlling the optical frequency of the source by using a pulse control block receiving the output signal from the photodiode and the interrogation sequence, and providing a correction signal to the source. During the period T1, the block extracts an error signal from the output signal received from the photodiode and generates the correction signal from the error signal. During the period T2, the block resets the error signal to zero and generates the correction signal by extrapolation.