A highly-efficient ridge waveguide includes a base substrate of a single-crystal and a core substrate made of a nonlinear optical medium, the base substrate and the core substrate being directly bonded, and includes a thin film layer formed on a surface of the core substrate on the upper side of a periodically polarization-reversed structure, and becomes a wavelength conversion element. A direct bonding method through thermal diffusion is applied to bonding. The core substrate has a ridge structure formed in a light propagating direction and a reversed structure formed by processing this. A surface of the core substrate is ground and a thin film layer is formed on the ground surface. A core formed by digging a core layer of the core substrate in an unbonded state is provided on an upper surface of an undercladding layer of the base substrate in a bonded state. Two side surfaces of the core are in contact with an air layer.

This invention addresses the abovementioned problem, and the purpose of this invention is to provide a far-infrared spectroscopy device that uses an is-TPG method to generate far-infrared light, and is capable of efficiently detecting is-TPG light without a detection optical system being fine-tuned. Even if the far-infrared light incidence angles on an Si prism for detection are the same when far-infrared light having a first frequency is incident on a non-linear optical crystal for detection and when far-infrared light having a second frequency is incident on the non-linear optical crystal for detection, this far-infrared. spectroscopy device adjusts the incidence surface angle of pump light in relation to the non-linear optical crystal for detection such that the angle of the far-infrared light in relation to the pump light within the non-linear optical crystal for detection can be appropriately set for each far-infrared light frequency (see FIG. 1A).

A tunable laser assembly uses a fundamental wavelength between 1 μm and 1.1 μm to alternately generate laser output light at two or more output wavelengths within the range of 184 nm to 200 nm by directing the fundamental light through different regions of a fan-out periodically poled nonlinear crystal to generate corresponding different down-converted signals, and using different nonlinear summing crystals to mix the different down-converted signals with a fifth harmonic of the fundamental wavelength. Each nonlinear summing crystal has a crystal axis aligned at an angle relative to the light propagation direction to facilitate the efficient transmission and summing of the fifth harmonic with an associated down-converted signal. In response to a user-selected output wavelength, a frequency control system positions the fan-out periodically poled nonlinear crystal to generate a corresponding down-converted signal frequency and positions an associated nonlinear summing crystal to receive the fifth harmonic and the corresponding down-converted signal.

An integrated optical circuit for an optical neural network is provided. The integrated optical circuit is configured to process a phase-encoded optical input signal and to provide a phase-encoded output signal depending on the phase-encoded optical input signal. The phase-encoded output signal emulates a synapse functionality with respect to the phase-encoded optical input signal. A related method and a related design structure are further provided.

An integrated optical circuit for an optical neural network is provided. The integrated optical circuit is configured to process a phase-encoded optical input signal and to provide a phase-encoded output signal depending on the phase-encoded optical input signal. The phase-encoded output signal emulates a synapse functionality with respect to the phase-encoded optical input signal. A related method and a related design structure are further provided.

Disclosed is an illumination source comprising a gas delivery system comprising a gas nozzle. The gas nozzle comprises an opening in an exit plane of the gas nozzle. The gas delivery system is configured to provide a gas flow from the opening for generating an emitted radiation at an interaction region. The illumination source is configured to receive a pump radiation having a propagation direction and to provide the pump radiation in the gas flow. A geometry shape of the gas nozzle is adapted to shape a profile of the gas flow such that gas density of the gas flow first increases to a maximum value and subsequently falls sharply in a cut-off region along the propagation direction.

Disclosed is an illumination source comprising a gas delivery system comprising a gas nozzle. The gas nozzle comprises an opening in an exit plane of the gas nozzle. The gas delivery system is configured to provide a gas flow from the opening for generating an emitted radiation at an interaction region. The illumination source is configured to receive a pump radiation having a propagation direction and to provide the pump radiation in the gas flow. A geometry shape of the gas nozzle is adapted to shape a profile of the gas flow such that gas density of the gas flow first increases to a maximum value and subsequently falls sharply in a cut-off region along the propagation direction.

A decrease of an output of a wavelength converted light converted by a nonlinear optical crystal is suppressed. A light source apparatus according to the present disclosure includes a fundamental wave light source configured to generate a fundamental wave which is a continuous oscillation laser beam, an external cavity including a plurality of optical mirrors, a nonlinear optical crystal installed inside the external cavity and configured to generate a light with a wavelength shorter than that of the fundamental wave. The light source apparatus includes at least one phase modulator disposed between the fundamental wave light source and the external cavity and configured to modulate the fundamental wave by a modulation frequency of an integer multiple of a resonance frequency interval of the external cavity.

An entanglement-enhanced interferometry system includes a source of correlated photons configured to two-mode squeezed vacuum (TMSV), a polarizing splitter or off-axis polarizing coupler configured to separate the correlated photons into two paths, a polarization control device configured to rotate polarization of photons on one of the two paths relative to the photons on the other of the two paths in order to make photons indistinguishable, a coupler configured to entangle the indistinguishable photons, and a polarization maintaining fiber-based interferometer configured to use the entangled photons as the input state. The source of correlated photons might be a nonlinear element such as a periodically poled element such as a lithium niobate bulk crystal or waveguide. The interferometer might be a Mach-Zehnder or a common path configuration. The coupler might be a 50:50 coupler or a polarizing coupler 45 degrees off-axis.

A structure for an optoelectronics platform and a method of fabricating a structure for an optoelectronics platform such as a Mach-Zehnder modulator or a waveguide. The method comprises the steps of providing a substrate, and depositing a BaTi03, BTO, film on a surface of the substrate and having a thickness suitable for single mode operation with one or more possible polarization configurations with optical confinement in the BTO film at a wavelength or wavelength range of operation; wherein the substrate is chosen to provide vertical refractive index confinement in a direction perpendicular to the surface of the substrate for the single mode operation optical confinement in the BTO film at the wavelength or wavelength range of operation.