In one aspect, a device is disclosed that includes one or more input ports structured to receive a pumping light at a pumping wavelength and a signal light at a signal wavelength, and one or more output ports structured to output light including an amplified signal light at the signal wavelength and a second harmonic idler light. The device includes a nonlinear optical material to mix the pumping light and the signal light and to cause nonlinear conversion of the pumping light into the amplified signal light and generate an idler light at an idler wavelength. The nonlinear optical material is further structured to convert the idler light into the second harmonic idler light which eliminates the idler light at the one or more output ports and prevents back-conversion of the amplified signal light and idler light to the pumping wavelength.

Disclosed here are methods, devices, and systems for generating an output light beam for a pulsed laser. An example method may comprise generating one or more pump optical beams comprising at least two photons having a pump wavelength. A first nonlinear stage may convert the at least two photons to a first photon having a first wavelength that is half of the pump wavelength. The first optical beam may be caused to spatially overlap with a seed optical beam. At least two second nonlinear stages separated by a gap may be used to convert, based on the seed optical beam, the first photon to a second photon having a second wavelength and a third photon having a target wavelength greater than the pump wavelength. A third nonlinear stage may convert the second photon to a fourth photon and a fifth photon each having the target wavelength or having a wavelength within an offset range of the target wavelength.

A visible light source includes a substrate, a vertical-cavity surface-emitting laser including an active semiconductor region configured to emit infrared light and a first reflector configured to reflect the infrared light emitted by the active semiconductor region, a second reflector configured to reflect the infrared light and form a vertical cavity for the infrared light with the first reflector, and one or more micro-resonators configured to receive the infrared light and generate visible light in one or more colors using the infrared light through optical parametric oscillation. The visible light source also includes one or more output couplers configured to couple the visible light in one or more colors from the one or more micro-resonators into free space or into a photonic integrated circuit.

Provided is a laser device in which: a laser medium doped with ytterbium emits light upon absorption of excitation light; the light emitted by the laser medium is amplified to obtain output light; and the output light is outputted in the form of a plurality of pulses. In the laser device, a spatial filter is disposed in the optical path of the light emitted by the laser medium or is disposed in the optical path of the output light outputted from an optical resonator, the spatial filter being configured to filter out a portion of the light or of the output light around the optical axis.

A laser system produces pulses having wavelengths between 2000 nm and 2100 nm, peak output powers greater than 1 kW, average powers greater than 10 W, pulse widths variable from 0.5 to 10 nsec, pulse repetition frequencies variable from 0.1 to over 2 MHz, and a pulse extinction of at least 60 dB. Pulses from a diode laser having a wavelength between 1000 nm and 1100 nm are amplified by at least one fiberoptic amplifier and applied as the pump input to an Optical Parametric Amplifier (OPA). A cw laser provides an OPA seed input at a wavelength between 2000 nm and 2200 nm. The idler output of the OPA having difference frequency wavelength between 2000 nm and 2100 nm is further amplified by a crystal amplifier. The fiberoptic amplifier can include Ytterbium-doped fiberoptic. The crystal amplifier can include a Ho:YAG, Ho:YLF, Ho:LuAG, and/or a Ho:Lu2O3 crystal.

A pulsed laser output section outputs a laser beam having a predetermined wavelength as first pulses. An optical path determining section receives the first pulses and determines one among a plurality of optical paths for each of the first pulses for output. A parallelizing section parallelizes a traveling direction of light beams traveling, respectively, through the plurality of optical paths. A wavelength changing section receives outputs from the parallelizing section and changes the outputs to have different wavelengths for output. A focusing section receives and focuses outputs from the wavelength changing section. An optical fiber receives an output from the focusing section at a core end face. A timing control section is arranged to time outputs from the optical path determining section to the output of the first pulses. The focusing section is arranged to focus the outputs from the wavelength changing section on the core end face.

A pulsed laser output section outputs a laser beam having a predetermined wavelength as first pulses. An optical path determining section receives the first pulses and determines one among a plurality of optical paths for each of the first pulses for output. A parallelizing section parallelizes a traveling direction of light beams traveling, respectively, through the plurality of optical paths. A wavelength changing section receives outputs from the parallelizing section and changes the outputs to have different wavelengths for output. A focusing section receives and focuses outputs from the wavelength changing section. An optical fiber receives an output from the focusing section at a core end face. A timing control section is arranged to time outputs from the optical path determining section to the output of the first pulses. The focusing section is arranged to focus the outputs from the wavelength changing section on the core end face.

Apparatus for producing a multiplicity of photons having quantum-entangled single-photon states is provided. The single photon includes two quantum-entangled degrees of freedom, and the apparatus includes a source apparatus of the multiplicity of photons having quantum-entangled single-photon states including first- and second-generation stages. The first stage includes a first element having a source generating a multiplicity of photons, the first element selects a first degree of freedom of two degrees of freedom of the single photon, which includes only one pair of values, and a second element that selects a second degree of freedom of two degrees of freedom of the single photon. The second degree of freedom includes only one pair of values, the second stage: generates a coherent superposition of the two degrees of freedom of the single photon; selects one value of a first and a second of said two degrees of freedom.

Various embodiments may provide an optical system. The optical system may include a laser source configured to emit a pump beam. The optical system may also include a non-linear medium configured to generate, based on the pump beam, an idler beam configured to incident on the sample and configured to be reflected, and a signal beam. The optical system may further include a mirror configured to reflect the signal beam so that the reflected signal beam interacts with the reflected idler beam in the non-linear medium to generate a resultant signal beam that carries an interference pattern. The optical system may additionally include a detector configured to receive the resultant signal beam for imaging the sample. The optical system may also include one or more optical elements configured to direct the idler beam from the non-linear medium to the sample, and the signal beam from the non-linear medium to the mirror.

Various embodiments may provide an optical system. The optical system may include a laser source configured to emit a pump beam. The optical system may also include a non-linear medium configured to generate, based on the pump beam, an idler beam configured to incident on the sample and configured to be reflected, and a signal beam. The optical system may further include a mirror configured to reflect the signal beam so that the reflected signal beam interacts with the reflected idler beam in the non-linear medium to generate a resultant signal beam that carries an interference pattern. The optical system may additionally include a detector configured to receive the resultant signal beam for imaging the sample. The optical system may also include one or more optical elements configured to direct the idler beam from the non-linear medium to the sample, and the signal beam from the non-linear medium to the mirror.