Systems and methods are provided for creating a sequence of turn-up processes for amplifiers. A method, according to one implementation, includes determining when a fiber span is initially installed in an optical line system or when an Optical Line Failure (OLF) in the fiber span has recovered. The optical line system includes a first set of amplifiers deployed at an upstream node and a second set of amplifiers deployed at a downstream node, the upstream node connected to the downstream node via the fiber span. In response to determining that the fiber span is initially installed in the optical line system or that an ORL in the fiber span has recovered, the method also includes sending a flag from the upstream node to the downstream node to allow the first set of amplifiers to perform a first turn-up process before the second set of amplifiers perform a second turn-up process.

Disclosed are dielectric cavity arrays with cavities formed by pairs of dielectric tips, wherein the cavities have low mode volume (e.g., 7*10.sup.−5λ.sup.3, where X is the resonance wavelength of the cavity array), and large quality factor Q (e.g., 10.sup.6 or more). Applications for such dielectric cavity arrays include, but are not limited to, Raman spectroscopy, second harmonic generation, optical signal detection, microwave-to-optical transduction, and as light emitting devices.

Methods and apparatus for a controlling a stimulus source to direct photons to a pixel in a pixel array contained in a detector system, analyzing a response of the pixel in the pixel array; and generating an alert based on the response of the pixel in the pixel array. Example stimulus sources include a conductive trace, a PN junction, and a current source.

A laser device includes a seed laser, a plurality of optical amplifiers, and an optical distribution assembly. The seed laser is configured to emit seed laser light. The plurality of optical amplifiers is configured to generate amplified laser light by amplifying the seed laser light. The optical distribution assembly is configured to distribute the seed laser light to an input of each of the optical amplifiers in the plurality and each of the optical amplifiers is configured to direct its respective amplified laser light to a common target.

An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The quantum well active layer is doped with 0.3 to 1×10.sup.18/cm.sup.3 of n-type impurity.

A method of making a microstructured optical fiber including loading the core and cladding materials of the fiber with hydrogen and deuterium at a loading temperature; annealing the fiber at a selected temperature T.sub.anneal; pumping the fiber with radiation; and reducing the temperature of the fiber and storing the fiber at the reduced temperature before the step of pumping the fiber; and wherein the method allows the hydrogen and the deuterium to become bound to the core material and the cladding material.

A stimulated Raman scattering (SRS) spectrometer for real-time, high-resolution molecular analysis of gases is based on two hollow-core fibres illuminated by a single high-power, short-pulse laser pump. The first fibre is prefilled with high-concentration target gases. Interaction of each target gas inside the first fibre, with the laser pump, generates Raman signals corresponding to the target gases. The combined beam of the Raman signals and the pump laser beam is directed into the second fibre containing the measured target gases. Interaction of each target gas with the combined beam generates the Stimulated Raman Growth (SRG), i.e., amplification of the Raman signal, which is proportional to the corresponding target gas concentration. A receiver subsystem receives the beam from the second fibre, spectrally separates it to wavelengths corresponding to each target gas, extracts the SRG value corresponding to each target gas and calculates the concentration of each target gas.

A single-laser light source system for cold atom interferometers, comprising: a reference light module including a narrow-bandwidth laser and a frequency stabilization module and an optical frequency shift module including a first electro-optic modulator and a first narrow-bandwidth optical-fiber filter. The first electro-optic modulator is connected to the first narrow-bandwidth optical-fiber filter by an optical fiber, and the first electro-optic modulator is connected to the laser by an optical fiber. The first electro-optic modulator receives an initial light from the laser, modulates the initial light by a modulation signal with a preset frequency, and generates sidebands with the preset frequency. The first narrow-bandwidth optical-fiber filter filters the optical signal at the output of the first electro-optic modulator to obtain a frequency-shifted light as the +1-order sideband. The frequency-shifted light is used for modulation to obtain a measurement and control light of the cold atom interferometer.

There are provided methods and system for providing high power, high brightness, visible laser source and laser beams. There are provided methods and systems of a direct conversion of poor beam quality visible laser light sources into a single high brightness beam in a resonant or ring laser cavity using a dual core or single core optical fiber and Stimulated Brillouin Scattering as the non-linear conversion mechanism in the graded index core of the fiber.

An optical system for suppressing signal noise on an optical fiber, including an input power signal; a pump laser configured to receive the input power signal; a phase modulator coupled to the pump laser configured to modulate, in response to the input power signal, a phase of the pump laser to increase a stimulated Brillouin scattering (SBS) threshold of the pump laser, wherein the pump laser is further configured to: increase a power at the pump laser to be greater than the SBS threshold; generate a back scattering power based on the power of the pump laser being greater than the increased SBS threshold; and limit an output power signal of the pump laser based on the generated back scattering power.