A method for implementing an atomic clock based on NV-.sup.14N coupling spin system in diamond and a device are provided. The method is to lock a RF frequency using a .sup.14N zero-field splitting and output the RF frequency as a frequency standard. The method includes: applying a pulse sequence to jointly initialize NV electron spins and .sup.14N nuclear spins; performing a Ramsey interferometry to compare a RF frequency and a .sup.14N zero-field splitting; entangling the NV electron spin and the nuclear spin, reading out a state of nuclear spins by collecting a fluorescence signal; calculating a frequency difference between the RF frequency and the .sup.14N zero-field splitting according to the fluorescence signal, thereby locking the RF frequency to the .sup.14N zero-field splitting; and outputting the RF frequency as a frequency standard.

A method for implementing an atomic clock based on NV-.sup.14N coupling spin system in diamond and a device are provided. The method is to lock a RF frequency using a .sup.14N zero-field splitting and output the RF frequency as a frequency standard. The method includes: applying a pulse sequence to jointly initialize NV electron spins and .sup.14N nuclear spins; performing a Ramsey interferometry to compare a RF frequency and a .sup.14N zero-field splitting; entangling the NV electron spin and the nuclear spin, reading out a state of nuclear spins by collecting a fluorescence signal; calculating a frequency difference between the RF frequency and the .sup.14N zero-field splitting according to the fluorescence signal, thereby locking the RF frequency to the .sup.14N zero-field splitting; and outputting the RF frequency as a frequency standard.

A photonically multiplexed optical measurement apparatus for performing optical multiplexing includes a laser that produces laser light, an optical switch that receives the laser light from the laser and produces a switched laser light, and a plurality of sensor heads, each sensor head being configured to measure a respective physical property of a plurality of cold atoms disposed in the sensor head. The optical switch optically switches the laser light from the laser to a selected sensor head and subsequently to a different sensor head.

A multi-quantum-reference (MQR) laser frequency stabilization system includes a laser system, an MQR system, and a controller. The laser system provides an output beam with an output frequency, and plural feedback beams with respective feedback frequencies. The feedback beams are directed to the MQR system which includes plural references, each including a respective population of quantum particles, e.g., rubidium 87 atoms, with respective resonant frequencies for respective quantum transitions. The degree to which the feedback frequencies match or deviate from the resonance frequencies can be tracked using fluorescence or other electro-magnetic radiation output from the references. The controller can stabilize the laser system output frequency based on plural reference outputs to achieve both short-term and long-term stability, e.g., in the context of an atomic clock.

A method of fabricating one or more glass cells includes drawing one or more glass capillaries from a source of glass material. The method includes performing a first conditioning of one or more inner surfaces of the one or more capillaries. The method includes sealing one or more first ends of the one or more capillaries using thermal energy. The method includes performing a second conditioning of the one or more inner surfaces after the sealing. The method includes purifying the one or more capillaries to increase a purity of a gas used to fill the one or more capillaries. The method includes filling the one or more capillaries using the gas after the purifying. The method includes pressurizing the one or more capillaries to a given pressure. The method includes sealing one or more second ends of the one or more capillaries using thermal energy.

A method of fabricating one or more glass cells includes drawing one or more glass capillaries from a source of glass material. The method includes performing a first conditioning of one or more inner surfaces of the one or more capillaries. The method includes sealing one or more first ends of the one or more capillaries using thermal energy. The method includes performing a second conditioning of the one or more inner surfaces after the sealing. The method includes purifying the one or more capillaries to increase a purity of a gas used to fill the one or more capillaries. The method includes filling the one or more capillaries using the gas after the purifying. The method includes pressurizing the one or more capillaries to a given pressure. The method includes sealing one or more second ends of the one or more capillaries using thermal energy.

Methods of using vapor cells may involve providing a vapor cell including a body defining a cavity within the body. At least a portion of at least one surface of the vapor cell within the cavity may include at least one pore having an average dimension of about 500 microns or less, as measured in a direction parallel to the at least one surface. A vapor pressure of a subject material within the cavity may be controlled utilizing the at least one pore by inducing an exposed surface of a subject material in a liquid state within the at least one pore to have a shape different than a shape the exposed surface of the subject material in a liquid state would have on a flat, nonporous surface.

Methods of using vapor cells may involve providing a vapor cell including a body defining a cavity within the body. At least a portion of at least one surface of the vapor cell within the cavity may include at least one pore having an average dimension of about 500 microns or less, as measured in a direction parallel to the at least one surface. A vapor pressure of a subject material within the cavity may be controlled utilizing the at least one pore by inducing an exposed surface of a subject material in a liquid state within the at least one pore to have a shape different than a shape the exposed surface of the subject material in a liquid state would have on a flat, nonporous surface.

According to some aspects of the present disclosure, an atomic clock and methods of forming and/or using an atomic clock are disclosed. In one embodiment, an atomic clock includes: a light source configured to illuminate a resonance vapor cell; a narrowband optical filter disposed between the light source and the resonance vapor cell and arranged such that light emitted from the light source passes through the narrowband optical filter and illuminates the resonance vapor cell. The resonance vapor cell is configured to emit a signal corresponding to a hyperfine transition frequency in response to illumination from the light source, and a filter cell is disposed between the light source and the resonance vapor cell and configured to generate optical pumping. An optical detector is configured to detect the emitted signal corresponding to the hyperfine transition frequency.

According to some aspects of the present disclosure, an atomic clock and methods of forming and/or using an atomic clock are disclosed. In one embodiment, an atomic clock includes: a light source configured to illuminate a resonance vapor cell; a narrowband optical filter disposed between the light source and the resonance vapor cell and arranged such that light emitted from the light source passes through the narrowband optical filter and illuminates the resonance vapor cell. The resonance vapor cell is configured to emit a signal corresponding to a hyperfine transition frequency in response to illumination from the light source, and a filter cell is disposed between the light source and the resonance vapor cell and configured to generate optical pumping. An optical detector is configured to detect the emitted signal corresponding to the hyperfine transition frequency.