Abstract: One embodiment is directed towards a stabilized laser including a laser to produce light at a frequency and a resonator coupled to the laser such that the light from the laser circulates therethrough. The laser also includes Pound-Drever-Hall (PDH) feedback electronics configured to adjust the frequency of the light from the laser to reduce phase noise in response to light sensed at the reflection port of the resonator and transmission port feedback electronics configured to adjust the frequency of the light from the laser toward resonance of the resonator at the transmission port in response to the light sensed at the transmission port of the resonator, wherein the transmission port feedback electronics adjust the frequency at a rate at least ten times slower than the PDH feedback electronics.

Abstract: A resonator fiber optic gyroscope (RFOG) is provided.

Abstract: A rare-earth-doped-fiber light source with wavelength stability includes a rare-earth doped fiber and an undoped fiber placed in proximity to each other and having the same host material and the same cross-sectional structure, a coupler configured to direct a first portion of pump power from a pump laser to the undoped fiber so the first portion of pump power was twice passed through the coupler; and a wavelength division multiplexer configured to input a second portion of pump power from the pump laser to the rare-earth doped fiber. The rare-earth doped fiber is an active medium for the broadband light source and includes a fiber core doped with rare-earth ions. The undoped fiber includes a rare-earth-dopant-free fiber core. The length of the undoped fiber is one of the same as that of the doped fiber or optimized to match a radiation sensitivity of the doped fiber.

Abstract: One embodiment is directed towards a resonator fiber optic gyroscope (RFOG) including a resonator, one or more light sources coupled to the resonator, and resonance tracking electronics coupled to the resonator. The one or more light sources are configured to produce at least two light beams for input into the fiber coil, the at least two light beams including a first light beam at a first frequency and a second light beam at a second frequency, the first and second frequencies locked to nearby resonance modes of the resonator. The resonance tracking electronics are configured to process output light from the resonator and generate a signal therefrom, the signal indicative of a rotation rate of the resonator. The fiber coil has approximately zero total accumulated chromatic dispersion at the first frequency and the second frequency of the first light beam and the second light beam.

Abstract: One embodiment is directed towards a stabilized laser including a laser to produce light at a frequency and a resonator coupled to the laser such that the light from the laser circulates therethrough. The laser also includes Pound-Drever-Hall (PDH) feedback electronics configured to adjust the frequency of the light from the laser to reduce phase noise in response to light sensed at the reflection port of the resonator and transmission port feedback electronics configured to adjust the frequency of the light from the laser toward resonance of the resonator at the transmission port in response to the light sensed at the transmission port of the resonator, wherein the transmission port feedback electronics adjust the frequency at a rate at least ten times slower than the PDH feedback electronics.

Abstract: An exemplary resonator fiber optic gyroscope comprises a resonator having an optical fiber loop; a light source configured to generate a light beam; and an intensity modulation circuit coupled between the light source and the resonator. The intensity modulation circuit is configured to modulate the intensity of the light beam from the light source to output an intensity modulated signal to the resonator. The intensity modulation circuit is configured to produce the intensity modulated signal such that harmonics of the intensity modulated signal which overlap a primary wave of a counter-propagating light beam in the resonator have an amplitude below a predetermined threshold. Amplitudes below the predetermined threshold are negligible.

Abstract: A low-noise resonator fiber-optic gyroscope is provided. The low-noise resonator fiber-optic gyroscope includes at least one laser to output a reference optical beam, a first-optical-beam frequency controller to modulate the first optical beam at a first-modulation frequency, a second-optical-beam frequency controller to modulate the second optical beam at a second-modulation frequency to form a second-frequency-modulated optical beam, a fiber resonator having a counter-clockwise-input end configured to input the first-frequency-modulated optical beam and the clockwise-input end configured to input the second-frequency-modulated optical beam; a first-frequency demodulator to demodulate an optical beam output from the clockwise-input end of the fiber resonator; and a second-frequency demodulator to demodulate an optical beam output from the counter-clockwise-input end of the fiber resonator.

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: Systems and methods for measuring rotation using an optical frequency comb stimulated Brillouin scattering gyroscope are provided. In certain embodiments, a system comprises a light source that produces a multiple-frequency light beam based on an optical frequency comb; and an optical fiber resonator coupled to the light source, the multiple-frequency light beam propagating in a first direction within the optical fiber resonator, wherein the multiple -frequency light beam generates stimulated Brillouin scattering (SBS) for a frequency, wherein the Brillouin scattering generates an SBS light beam to propagate in a second direction, the first direction being opposite in direction to the second direction. The system also comprises a servo to control the frequencies of the optical frequency comb to lock a plurality of component frequencies on resonance peaks of the optical fiber resonator; and a mixer that determines a frequency difference between the SBS light beam and the multiple-frequency light beam.

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: A laser apparatus comprises a pump laser device, and a polarizing optical fiber having a proximal end and a distal end, with the polarizing optical fiber coupled to the pump laser device at the proximal end. At least one output reflector is written on the polarizing optical fiber toward the distal end. Only one polarization mode is supported when a laser beam is transmitted through the polarizing optical fiber from the pump laser device.

Abstract: A rare-earth-doped-fiber light source with wavelength stability includes a rare-earth doped fiber and an undoped fiber placed in proximity to each other and having the same host material and the same cross-sectional structure, a coupler configured to direct a first portion of pump power from a pump laser to the undoped fiber so the first portion of pump power was twice passed through the coupler; and a wavelength division multiplexer configured to input a second portion of pump power from the pump laser to the rare-earth doped fiber. The rare-earth doped fiber is an active medium for the broadband light source and includes a fiber core doped with rare-earth ions. The undoped fiber includes a rare-earth-dopant-free fiber core. The length of the undoped fiber is one of the same as that of the doped fiber or optimized to match a radiation sensitivity of the doped fiber.

Abstract: Systems and methods for measuring rotation using an optical frequency comb stimulated Brillouin scattering gyroscope are provided. In certain embodiments, a system comprises a light source that produces a multiple-frequency light beam based on an optical frequency comb; and an optical fiber resonator coupled to the light source, the multiple-frequency light beam propagating in a first direction within the optical fiber resonator, wherein the multiple-frequency light beam generates stimulated Brillouin scattering (SBS) for a frequency, wherein the Brillouin scattering generates an SBS light beam to propagate in a second direction, the first direction being opposite in direction to the second direction. The system also comprises a servo to control the frequencies of the optical frequency comb to lock a plurality of component frequencies on resonance peaks of the optical fiber resonator; and a mixer that determines a frequency difference between the SBS light beam and the multiple-frequency light beam.

Abstract: A laser stabilization system includes laser source having first and second ends; first waveguide portion having first and second ends, first end of first waveguide portion coupled to first end of laser source; second waveguide portion having first and second ends, first end of second waveguide portion coupled to second end of laser source; micro-cavity coupled between second end of first waveguide portion and second end of second waveguide portion, micro-cavity having resonant frequency; and electronic locking loop coupled between micro-cavity and laser source, wherein electronic locking loop electronically locks laser source to resonant frequency of micro-cavity; wherein first waveguide portion is optical locking loop coupled between micro-cavity and laser source, wherein optical locking loop optically locks laser source to resonant frequency of micro-cavity; micro-cavity stabilization loop coupled with micro-cavity, wherein micro-cavity stabilization loop stabilizes resonant frequency of micro-cavity to ref

Abstract: A resonator fiber optic gyroscope comprises a first light source having a first frequency comb spectrum, and a second light source having a second frequency comb spectrum. A first filter is in optical communication with the first light source and configured to pass a first frequency comb portion. A second filter is in optical communication with the second light source and configured to pass a second frequency comb portion. A resonator is in optical communication with the first and second filters. The free spectral range values of the first and second frequency comb portions are adjusted to be an odd integer multiple of the free spectral range value of the resonances of the resonator. The second frequency comb portion is spectrally separated apart from the first frequency comb portion by a multiple of the free spectral range value of the resonances plus a frequency value proportional to rotation rate.

Abstract: A low-noise resonator fiber-optic gyroscope is provided. The low-noise resonator fiber-optic gyroscope includes at least one laser to output a reference optical beam, a first-optical-beam frequency controller to modulate the first optical beam at a first-modulation frequency, a second-optical-beam frequency controller to modulate the second optical beam at a second-modulation frequency to form a second-frequency-modulated optical beam, a fiber resonator having a counter-clockwise-input end configured to input the first-frequency-modulated optical beam and the clockwise-input end configured to input the second-frequency-modulated optical beam; a first-frequency demodulator to demodulate an optical beam output from the clockwise-input end of the fiber resonator; and a second-frequency demodulator to demodulate an optical beam output from the counter-clockwise-input end of the fiber resonator.

Abstract: One embodiment is directed towards a stabilized laser including a laser to produce light at a frequency and a resonator coupled to the laser such that the light from the laser circulates therethrough. The laser also includes Pound-Drever-Hall (PDH) feedback electronics configured to adjust the frequency of the light from the laser to reduce phase noise in response to light sensed at the reflection port of the resonator and transmission port feedback electronics configured to adjust the frequency of the light from the laser toward resonance of the resonator at the transmission port in response to the light sensed at the transmission port of the resonator, wherein the transmission port feedback electronics adjust the frequency at a rate at least ten times slower than the PDH feedback electronics.

Abstract: A resonator fiber optic gyroscope comprises a first light source having a first frequency comb spectrum, and a second light source having a second frequency comb spectrum. A first filter is in optical communication with the first light source and configured to pass a first frequency comb portion. A second filter is in optical communication with the second light source and configured to pass a second frequency comb portion. A resonator is in optical communication with the first and second filters. The free spectral range values of the first and second frequency comb portions are adjusted to be an odd integer multiple of the free spectral range value of the resonances of the resonator. The second frequency comb portion is spectrally separated apart from the first frequency comb portion by a multiple of the free spectral range value of the resonances plus a frequency value proportional to rotation rate.

Abstract: An optical-fiber filter is provided. The optical-fiber filter includes an optical fiber having a first end-face and an opposing second end-face. The first end-face and the second end-face set a fiber length. The first end-face and the second end-face are coated with reflective coatings. When an optical beam emitted from a laser is coupled into one of the first end-face or the second end-face, an optical beam output from the opposing end-face has a narrow linewidth and low frequency noise fluctuations.

Abstract: Systems and methods for reducing intensity modulation-induced rotation rate measurement error in a resonator optical gyroscope. The method includes tapping an intensity modulated light beam, directing a portion of the tapped light beam toward a photo detector, outputting from the photo detector a signal proportional to the amplitude variation of the light beam, amplifying the signal, and then providing the signal to the intensity modulator as a control input. Intensity modulation-induced error is reduced by an amount proportional to the gain of the feedback loop.