A fluorescence detection process begins by localizing rubidium 87 atoms within an optical (all-optical or magneto-optical) trap so that at least most of the atoms in the trap are within a cone defined by an effective angle, e.g., 8°, of a spectral filter. Within the effective angle of incidence, the filter effectively rejects (reflects or absorbs) 778 nanometer (nm) fluorescence and effectively transmits 775.8 nm fluorescence. Any 775.8 nm fluorescence arrive outside the effective angle of incidence. Thus, using an optical trap to localize the atoms within the cone enhances the signal-to-noise ratio of the fluorescence transmitted through the spectral filter and arriving a photomultiplier or other photodetector, resulting fluorescence detection signal with an enhanced S/N.

A rubidium optical atomic clock uses a modulated 778 nanometer (nm) probe beam and its reflection to excite rubidium 87 atoms, some of which emit 758.8 nm fluorescence as they decay back to the ground state. A spectral filter rejects scatter of the 778 nm probe beams while transmitting the 775.8 nm fluorescence so that the latter can be detected with a high signal-to-noise ratio. Since the spectral filter is only acceptably effective at angles of incidence less than 8° from the perpendicular, the atoms are localized by a magneto-optical trap so that most of the atoms lie within a conical volume defined by the 8° angle so that the resulting fluorescence detection signal has a high signal-to-noise ratio. The fluorescence detection signal can be demodulated to provide an error signal from which desired adjustments to the oscillator frequency can be calculated.

A rubidium optical atomic clock uses a modulated 778 nanometer (nm) probe beam and its reflection to excite rubidium 87 atoms, some of which emit 758.8 nm fluorescence as they decay back to the ground state. A spectral filter rejects scatter of the 778 nm probe beams while transmitting the 775.8 nm fluorescence so that the latter can be detected with a high signal-to-noise ratio. Since the spectral filter is only acceptably effective at angles of incidence less than 8° from the perpendicular, the atoms are localized by a magneto-optical trap so that most of the atoms lie within a conical volume defined by the 8° angle so that the resulting fluorescence detection signal has a high signal-to-noise ratio. The fluorescence detection signal can be demodulated to provide an error signal from which desired adjustments to the oscillator frequency can be calculated.

In described examples, a magnetic sensor includes a waveguide that encapsulates dipolar molecules. A mm-wave electromagnetic field is launched into the waveguide, travels through the dipolar molecules, and is then received after passing through the dipolar molecules. The frequency of the mm-wave electromagnetic signal is swept across a range that includes an intrinsic quantum rotational state transition frequency (Fr) for the dipolar molecules. Absorption peaks in accordance with the Zeeman effect are determined. A strength of a magnetic field affecting the magnetic sensor is proportional to a difference in the frequencies of the absorption peaks.

An optical resonator device (100) with crossed cavities, in particular being configured for optically trapping atoms, comprises a first linear optical resonator (10) extending between first resonator mirrors (11A, 11B) along a first resonator light path (12) and supporting a first resonator mode, a second linear optical resonator (20) extending between second resonator mirrors (21A, 21B) along a second resonator light path (22) and supporting a second resonator mode, wherein the first and second resonator light paths (12, 22) span a main resonator plane, and a carrier device carrying the first and second resonator mirrors (11A, 11B, 21A, 21B), wherein the first and second resonator mirrors (11, 21) are arranged such that the first and second resonator modes cross each other for providing an optical lattice trap (1) in the main resonator plane. The carrier device comprises a monolithic spacer body (30) being made of an ultra-low-expansion material and comprising first carrier surfaces (31) accommodating the first resonator mirrors (11A, 11B) and second carrier surfaces (32) accommodating the second resonator mirrors (21A, 21B), wherein the first resonator light path (12) extends through a first spacer body bore (33) in the spacer body (30) between the first carrier surfaces (31), and the second resonator light path (22) extends through a second spacer body bore (34) in the spacer body (30) between the second carrier surfaces (32). Furthermore, an atom trapping method for creating a two-dimensional arrangement of atoms and an atom trap apparatus, like an optical atomic clock, a quantum simulation and/or a quantum computing device are described.

An optical resonator device (100) with crossed cavities, in particular being configured for optically trapping atoms, comprises a first linear optical resonator (10) extending between first resonator mirrors (11A, 11B) along a first resonator light path (12) and supporting a first resonator mode, a second linear optical resonator (20) extending between second resonator mirrors (21A, 21B) along a second resonator light path (22) and supporting a second resonator mode, wherein the first and second resonator light paths (12, 22) span a main resonator plane, and a carrier device carrying the first and second resonator mirrors (11A, 11B, 21A, 21B), wherein the first and second resonator mirrors (11, 21) are arranged such that the first and second resonator modes cross each other for providing an optical lattice trap (1) in the main resonator plane. The carrier device comprises a monolithic spacer body (30) being made of an ultra-low-expansion material and comprising first carrier surfaces (31) accommodating the first resonator mirrors (11A, 11B) and second carrier surfaces (32) accommodating the second resonator mirrors (21A, 21B), wherein the first resonator light path (12) extends through a first spacer body bore (33) in the spacer body (30) between the first carrier surfaces (31), and the second resonator light path (22) extends through a second spacer body bore (34) in the spacer body (30) between the second carrier surfaces (32). Furthermore, an atom trapping method for creating a two-dimensional arrangement of atoms and an atom trap apparatus, like an optical atomic clock, a quantum simulation and/or a quantum computing device are described.

The invention relates to a coherent population trapping (CPT) phase modulation and demodulation method and a system for implementing the method of this invention. The method comprises the following steps: Generating a coherent bichromatic light, in which the relative phase between the two frequency components is modulated with proper modulation depth. The phase modulated coherent bichromatic light interacts with a quantum resonance system, and prepares it alternately into two inverted CPT states. Detecting the transmitted light with a photodetector, two inverted dispersive CPT signals in two detection windows are observed. With synchronous phase demodulation, a CPT error signal is obtained, which is used for locking the local oscillator to implement a CPT atomic clock.

Systems and methods for precision control of microresonator (MR) based frequency combs can implement optimized MR actuators or MR modulators to control long-term locking of carrier envelope offset frequency, repetition rate, or resonance offset frequency of the MR. MR modulators can also be used for amplitude noise control. MR parameters can be locked to external reference frequencies such as a continuous wave laser or a microwave reference. MR parameters can be selected to reduce cross talk between the MR parameters, facilitating long-term locking. The MR can be locked to an external two wavelength delayed self-heterodyne interferometer for low noise microwave generation. An MR-based frequency comb can be tuned by a substantial fraction or more of the free spectral range (FSR) via a feedback control system. Scanning MR frequency combs can be applied to dead-zone free spectroscopy, multi-wavelength LIDAR, high precision optical clocks, or low phase noise microwave sources.

Systems and methods for precision control of microresonator (MR) based frequency combs can implement optimized MR actuators or MR modulators to control long-term locking of carrier envelope offset frequency, repetition rate, or resonance offset frequency of the MR. MR modulators can also be used for amplitude noise control. MR parameters can be locked to external reference frequencies such as a continuous wave laser or a microwave reference. MR parameters can be selected to reduce cross talk between the MR parameters, facilitating long-term locking. The MR can be locked to an external two wavelength delayed self-heterodyne interferometer for low noise microwave generation. An MR-based frequency comb can be tuned by a substantial fraction or more of the free spectral range (FSR) via a feedback control system. Scanning MR frequency combs can be applied to dead-zone free spectroscopy, multi-wavelength LIDAR, high precision optical clocks, or low phase noise microwave sources.

Systems and methods for an integrated optical atomic sensor are provided. In one embodiment, an optical atomic sensor comprises: first and second photonic integrated circuits and an atom trapping chamber positioned between and bonded to the photonic integrated circuits with the integrated circuits aligned parallel to each other; and atomic vapor sealed within the chamber; wherein the first and second photonic integrated circuits each comprise: a plurality of grating emitters fabricated into respective surfaces of the first and second photonic integrated circuits waveguides configured to couple laser light from laser light sources to the grating emitters; wherein at least one set of the grating emitters are arranged to launch laser light beams into the chamber in a pattern structured to cool the vapor and produce at least one atom trap; wherein the grating emitters further include at least one grating emitter configured to emit a laser light probe into vapor.