Systems and methods for ring laser gyroscopes (RLGs) are provided. An RLG includes a traveling-wave resonator cavity with three or more mirrors and a gain medium positioned in the traveling-wave resonator cavity between two of the three or more mirrors. The gain medium is a solid-state gain medium or a nonlinear optical medium. The RLG further includes a first pump laser and a second pump laser to pump the gain medium in different directions and generate first and second lasing signals that traverse the traveling-wave resonator cavity in a opposite directions. The RLG further includes first and second photodetectors to measure levels of the first and second lasing signals. The RLG further includes at least one processor configured to adjust a power level of the first pump laser and/or a power level of the second pump laser based on the measured power levels of the first and second lasing signals.

An integrated photonics optical gyroscope fabricated on a silicon nitride (SiN) waveguide platform comprises a first silicon nitride (SiN) waveguide layer that constitute a rotation sensing element; and, a second SiN waveguide layer with additional silicon nitride (SiN) waveguide-based optical components that constitute a front-end chip to launch light into and receive light from the rotation sensing element. The two SiN waveguide layers can be stacked together to have a multi-layer configuration vertically coupled with each other. External elements (e.g., laser, detectors, phase shifter) may be made of different material platform than SiN and can be hybridly integrated to the SiN waveguide platform. The phase shifters can be made of lithium niobate or other electro optic material.

A cable including an integrated intelligent cable module. The module preferably includes an integral instrument package. The instrument package may assume many forms and may serve many purposes. In a preferred embodiment, the module includes a position-determining system and an on-board processor. The processor determines a current location in space for the module based on the information it is receiving. This positional information may then be transmitted to an external receiver. The module also preferably includes load-monitoring and recording features. These features act as a “black box” for the cable, monitoring its performance and reporting (in real-time or at a later time) any exceedances or any deterioration in performance or structural integrity.

A coherent light source provides spontaneous emission (Dicke superradiance/subradiance) using a dilute and optically thin cloud of disordered atoms. The coherent light source provides improved noise statistics over that of a laser and, accordingly, may be used in sensitive interferometric applications such as light gyroscopes.

A method and a system for generating single-sideband Raman light for cold atom interferometer through phase modulation are provided. The system includes a laser, an electro-optic modulator (EOM), a local microwave oscillator, a narrow-bandwidth optical-fiber filter, an optical-fiber power amplifier and a frequency doubling crystal. The laser has frequency of ω and is input to the EOM. The local microwave oscillator applies a modulation voltage with frequency of δ to the EOM and generate double-sideband frequency-modulated light with frequencies of ω±nδ(n=0,1,2, . . . ). This light is filtered by the narrow-bandwidth optical-fiber filter, which outputs the target frequency light and is successively input to the optical-fiber power amplifier and the frequency doubling crystal and yields the single-sideband Raman light for cold atom interferometer. The Raman light generation system has simple structure, low-cost, high integration level, easy implementation, high maturity and good stability, and has practical significance in realizing an engineering-based laser system for high-precision atom interferometer measurement.

Proposed are an apparatus and a method of manufacturing a shell for a resonator using a laser. According to the apparatus and method, it is possible to stably manufacture 3D shells for a resonator in various shapes by applying heat through a laser and adjusting the degree of vacuum in a forming frame, it is possible to improve work safety and work efficiency, and it is possible to use various materials that are heated and deformed by a laser other than a glass material, thereby being able to increase generality of manufacturing. In particular, it is possible to accurately implement 3D shapes of a shell for a resonator such as a hemisphere or a semi-toroid, so it is possible to remarkably reduce a defective portion in manufacturing and the manufacturing cost, and considerably improve productivity.

Aspects of the present disclosure are directed to process flow to fabricate a waveguide structure with a silicon nitride core having atomic-level smooth sidewalls achieved by wet etching instead of the conventional dry etching process.

Systems and methods for ring laser gyroscopes (RLGs) are provided. An RLG includes a traveling-wave resonator cavity with three or more mirrors and a gain medium positioned in the traveling-wave resonator cavity between two of the three or more mirrors. The gain medium is a solid-state gain medium or a nonlinear optical medium. The RLG further includes a first pump laser and a second pump laser to pump the gain medium in different directions and generate first and second lasing signals that traverse the traveling-wave resonator cavity in a opposite directions. The RLG further includes first and second photodetectors to measure levels of the first and second lasing signals. The RLG further includes at least one processor configured to adjust a power level of the first pump laser and/or a power level of the second pump laser based on the measured power levels of the first and second lasing signals.

Techniques for reducing the bias error present in optical gyroscopes is disclosed. Such techniques include at least one path length adjustment member placed in an optical gyroscope resonator, which are configured to modulate the optical path length of the resonator so that bias errors attributable to the optical path length are shifted outside of the bandwidth of the optical gyroscope. In some embodiments, the at least one path length adjustment member includes a plurality of microheaters coupled to the resonator, in which case optical path length modulation is achieved by heating the resonator via the microheaters. Alternatively, a plurality of piezo-electric regions can be placed in the resonator, which enables optical path length modulation through electric field gradients applied to the piezo-electric regions.

Improvements to optical power regulation in a gyroscopic system are described. The system can include an optical assembly (e.g., optical bench) which couples opposing optical signals to a resonator coil. The system can monitor the power of the optical signals through the resonator coil by including signal extraction optics in the optical assembly which are configured to extract a portion of the optical signals. The portions can be extracted via a single beamsplitter, wherein the beamsplitter reflects the portions at a single common surface, and can also reflect the portions to a respective photodetector in free space free from intervening optical components, such as polarizers or beamsplitters. One or more processors can be coupled to the optical assembly, wherein the processor(s) are configured to adjust the power of the optical signals in response to detecting a power difference between the optical signals.