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.

A pulsed third-harmonic laser system includes a pulsed laser, an extra-cavity nonlinear crystal, and an intracavity nonlinear crystal. The pulsed laser generates fundamental laser pulses and couples out a portion of each fundamental laser pulse out of the laser resonator to undergo second-harmonic-generation in the extra-cavity nonlinear crystal. Resulting second-harmonic laser pulses are directed back into the laser resonator and mixes with the fundamental laser pulses in the intracavity nonlinear crystal to generate third-harmonic laser pulses. The pulsed third-harmonic laser system thus maintains a non-zero output coupling efficiency regardless of the efficiency of the second-harmonic-generation stage, while the third-harmonic-generation stage benefits from the intracavity power of the fundamental laser pulses.

A compact, portable Raman spectrometer makes fast, sensitive standoff measurements at little to no risk of eye injury or igniting the materials being probed. This spectrometer uses differential Raman spectroscopy and ambient light measurements to measure point-and-shoot Raman signatures of dark or highly fluorescent materials at distances of 1 cm to 10 m or more. It scans the Raman pump beam(s) across the sample to reduce the risk of unduly heating or igniting the sample. Beam scanning also transforms the spectrometer into an instrument with a lower effective safety classification, reducing the risk of eye injury. The spectrometer's long standoff range automatic focusing make it easier to identify chemicals through clear and translucent obstacles, such as flow tubes, windows, and containers. And the spectrometer's components are light and small enough to be packaged in a handheld housing or housing suitable for a small robot to carry.

A laser assembly is provided that includes a laser pump chamber that emits a first light through a laser cavity at a first wavelength, and a polarization assembly that receives the first light and converts the first light into a pulsed light that includes the first light at the first wavelength and a first polarization. The laser assembly also includes a second light at the first wavelength and a second polarization.

A technique is disclosed for electro-optically inducing a force to fabricated samples and/or devices with laser light. The technique uses the interaction of the oscillating electric field of the laser beam in opposition with the electric field produced by an appropriate electric charge carrier to achieve a net repulsive (or attractive) force on the component holding the electric charge. In one embodiment, force is achieved when the field near the charge carrier is modulated at a subharmonic of the electric field oscillation frequency of the laser and the relative phases of the light field and electric charge carrier field are controlled to provide optimal repulsion/attraction. The effect is scalable by applying the technique to an array of charge carrier fields sequentially as well as using higher power lasers and higher carrier field voltages.

A technique is disclosed for electro-optically inducing a force to fabricated samples and/or devices with laser light. The technique uses the interaction of the oscillating electric field of the laser beam in opposition with the electric field produced by an appropriate electric charge carrier to achieve a net repulsive (or attractive) force on the component holding the electric charge. In one embodiment, force is achieved when the field near the charge carrier is modulated at a subharmonic of the electric field oscillation frequency of the laser and the relative phases of the light field and electric charge carrier field are controlled to provide optimal repulsion/attraction. The effect is scalable by applying the technique to an array of charge carrier fields sequentially as well as using higher power lasers and higher carrier field voltages.

Embodiments include apparatuses, methods, and systems including a laser device having a 1×3 MMI coupler within a semiconductor layer. A front arm is coupled to the MMI coupler and terminated by a front reflector. In addition, a coarse tuning arm is coupled to the MMI coupler and terminated by a first back reflector for coarse wavelength tuning, a fine tuning arm is coupled to the MMI coupler and terminated by a second back reflector for fine wavelength tuning, and a SMSR and power tuning arm is coupled to the MMI coupler and terminated by a third back reflector. A gain region is above the front arm and above the semiconductor layer. Other embodiments may also be described and claimed.

Embodiments include apparatuses, methods, and systems including a laser device having a 1×3 MMI coupler within a semiconductor layer. A front arm is coupled to the MMI coupler and terminated by a front reflector. In addition, a coarse tuning arm is coupled to the MMI coupler and terminated by a first back reflector for coarse wavelength tuning, a fine tuning arm is coupled to the MMI coupler and terminated by a second back reflector for fine wavelength tuning, and a SMSR and power tuning arm is coupled to the MMI coupler and terminated by a third back reflector. A gain region is above the front arm and above the semiconductor layer. Other embodiments may also be described and claimed.

A method of providing in-line Raman amplification in an optical fiber sensing system, including the procedures of generating a probe light having a probe wavelength, transmitting the probe light into an optical fiber, generating at least one Raman pump light at a respective pump wavelength, the pump wavelength being shorter than the probe wavelength, generating at least one Raman seed light at a respective seed wavelength, the seed wavelength being between the pump and probe wavelengths, transmitting the Raman pump light into the optical fiber, transmitting the Raman seed light into the optical fiber and propagating the Raman pump light, the Raman seed light and the probe light along the optical fiber to achieve distributed Raman amplification of signal light produced by the probe light as it propagates along the optical fiber.

A frequency double or mixing laser includes a laser pump, a rear optical element, a Brewster window, a laser generator medium, an output coupler and a nonlinear crystal located inside the resonator cavity. The nonlinear crystal may be located inside the resonator cavity before the output coupler. The laser may further include at least one optical element that controls the phase or/and the amplitude of the fundamental laser beam to a high-order.