Abstract:
A radio-frequency atomic magnetometer comprises a laser, a photodetector, a vapor chamber, wherein the vapor chamber is in an optical path of laser light between the laser and photodetector, a circular polarizer configured to circularly polarize laser light emitted by the laser, wherein a circularly polarized laser beam is configured to pump into an oriented state, spins of atoms in the vapor chamber and to probe the atoms of the vapor chamber, wherein probing includes detecting a local radio frequency field; and a set of direct current (DC) field coils comprising at least one DC field coil, wherein the set of DC field coils is configured to generate a DC magnetic field oriented at 45 degrees relative to the optical axis of the laser light emitted by the laser and directed toward the vapor chamber; the set of DC field coils further configured to have adjustable DC magnetic field strength.
Abstract:
A laser gyroscope comprising includes a first solid waveguide; a gain medium interaction region where light traveling through the first solid waveguide interacts with non-solid Doppler-broadened gain medium molecules positioned outside of the first solid waveguide; at least one medium exciter configured to excite the non-solid Doppler-broadened gain medium at the gain medium interaction region, wherein the excited non-solid Doppler-broadened gain medium induces first and second laser fields within the first solid waveguide, wherein the first laser field travels in a clockwise direction within the first solid waveguide and the second laser field travels in a counter-clockwise direction within the first solid waveguide; and a photodetector communicatively coupled to the first solid waveguide and configured to detect the portions of the first and second laser fields.
Abstract:
A resonator fiber optic gyroscope (RFOG) is provided. The RFOG includes a gyroscope resonator having a clockwise input port and a counter-clockwise input port; a first laser configured to couple a clockwise optical beam into to the clockwise input port; a clockwise Pound-Drever-Hall modulation generator to modulate the clockwise optical beam with a resonance tracking modulation before the clockwise optical beam is coupled into the clockwise input port; bias correction electronics; FSR-detection-and-servo electronics including a switch communicatively coupled to the clockwise Pound-Drever-Hall modulation generator; a clockwise transmission detector configured to receive an optical beam output from the counter-clockwise input port and output signals to the bias correction electronics and the FSR-detection-and-servo electronics; and a second laser configured to couple a counter-clockwise optical beam into to the counter-clockwise input port, wherein the FSR of the gyroscope resonator is measured based on the Pound-Drever-Hall modulation of the clockwise optical beam.
Abstract:
An embodiment of a waveguide has a Brillouin bandwidth, and includes cladding and a core. The cladding includes first layers of a first material, each first layer having a physical characteristic of approximately a first value, and includes second layers of a second material, each second layer having the physical characteristic of approximately a second value, the second layers alternating with the first layers such that the Brillouin bandwidth is wider than the Brillouin bandwidth would be if the cladding excluded the first layers or excluded the second layers. For example, the first and second cladding layers can be formed from different materials, or can be formed having different values of a physical characteristic such as thickness, acoustic velocity, or index of refraction. Such a waveguide can facilitate alignment of the waveguide's optical bandwidth with the waveguide's Brillouin bandwidth because the Brillouin bandwidth is widened compared to conventional waveguides.
Abstract:
An embodiment of an integrated waveguide is configured for reducing the level of Brillouin scattering, and for reducing the levels of at least some of the unwanted effects of Brillouin scattering. Such an integrated waveguide has a Brillouin gain, includes a cladding, and includes a core disposed within the cladding and configured to cause the Brillouin gain to be less than the Brillouin gain would be if the core were straight. For example, the core can be configured as a non-straight (e.g., meandering) core to reduce the Brillouin gain in an integrated waveguide, and, therefore, to reduce a level of coherent Brillouin scattering of an electromagnetic wave propagating through the waveguide. Therefore, a core so configured can reduce the energy of a counter-propagating Stokes wave induced by the propagating electromagnetic wave as compared to an otherwise comparable waveguide having a straight core.
Abstract:
In an example, a chip-scale atomic clock physics package is provided. The physics package includes a body defining a cavity having a base surface and one or more side walls. The cavity includes a first step surface and a second step surface defined in the one or more side walls. A first scaffold mounted to the base surface in the cavity. One or more spacers defining an aperture therethrough are mounted to the second step surface in the cavity. A second scaffold is mounted to a first surface of the one or more spacers spans across the aperture of the one or more spacers. A third scaffold is mounted to a second surface of the one or more spacers in the cavity and spans across the aperture of the one or more spacers. Other components of the physics package are mounted to the first, second, and third scaffold.
Abstract:
In one embodiment a system including a resonator fiber-optic gyroscope configured to measure rotation rate is provided. The resonator fiber-optic gyroscope includes a sensing resonator have a first resonance frequency for a first laser beam propagation direction and a second resonance frequency for a second laser beam propagation direction, an optical mixer coupled to an output of the sensing resonator and configured to mix an output of the sensing resonator with a reference laser, wherein the optical mixer outputs a beat signal, and a resonance tracking electronics coupled to the optical mixer. The resonance tracking electronics are configured to demodulate the beat signal at a frequency offset to produce first in-phase and quadrature demodulated information, generate R-squared information from a sum of squares of the first in-phase and quadrature demodulated information, and demodulate the R-squared information at a resonance tracking modulation frequency.
Abstract:
In one embodiment, a method is provided. The method comprises: spin polarizing alkali atoms in a cavity; shifting resonant frequencies of the cavity at a rate proportional to a magnitude of a magnetic field incident upon the cavity; reflecting modulated right hand circularly polarized light and modulated left hand circularly polarized light from the cavity; transforming the reflected modulated right hand circularly polarized light to reflected modulated vertically polarized light, and the reflected modulated left hand circularly polarized light to reflected modulated horizontally polarized modulated light; generating a first error signal having an amplitude proportional to the shift in a resonant frequency corresponding to the reflected modulated vertically polarized light and a sign indicative of whether a frequency of the reflected modulated vertically polarized light is above or below the corresponding resonant frequency; generating a second error signal having an amplitude proportional to the shift in a resonant frequency corresponding to the reflected modulated horizontally polarized light and a sign indicative of whether a frequency of the reflected modulated horizontally polarized light is above or below the corresponding resonant frequency; adjusting a carrier frequency of the modulated right hand circularly polarized light in response to the first error signal; adjusting a carrier frequency of the modulated left hand circularly polarized light in response to the second error signal; and generating a measured Larmor frequency.
Abstract:
In one embodiment, a method is provided. The method comprises: spin polarizing alkali atoms in a cavity; shifting resonant frequencies of the cavity at a rate proportional to a magnitude of a magnetic field incident upon the cavity; reflecting modulated right hand circularly polarized light and modulated left hand circularly polarized light from the cavity; transforming the reflected modulated right hand circularly polarized light to reflected modulated vertically polarized light, and the reflected modulated left hand circularly polarized light to reflected modulated horizontally polarized modulated light; generating a first error signal having an amplitude proportional to the shift in a resonant frequency corresponding to the reflected modulated vertically polarized light and a sign indicative of whether a frequency of the reflected modulated vertically polarized light is above or below the corresponding resonant frequency; generating a second error signal having an amplitude proportional to the shift in a resonant frequency corresponding to the reflected modulated horizontally polarized light and a sign indicative of whether a frequency of the reflected modulated horizontally polarized light is above or below the corresponding resonant frequency; adjusting a carrier frequency of the modulated right hand circularly polarized light in response to the first error signal; adjusting a carrier frequency of the modulated left hand circularly polarized light in response to the second error signal; and generating a measured Larmor frequency.
Abstract:
An embodiment of a waveguide has a Brillouin bandwidth, and includes cladding and a core. The cladding includes first layers of a first material, each first layer having a physical characteristic of approximately a first value, and includes second layers of a second material, each second layer having the physical characteristic of approximately a second value, the second layers alternating with the first layers such that the Brillouin bandwidth is wider than the Brillouin bandwidth would be if the cladding excluded the first layers or excluded the second layers. For example, the first and second cladding layers can be formed from different materials, or can be formed having different values of a physical characteristic such as thickness, acoustic velocity, or index of refraction. Such a waveguide can facilitate alignment of the waveguide's optical bandwidth with the waveguide's Brillouin bandwidth because the Brillouin bandwidth is widened compared to conventional waveguides.