A supercontinuum radiation source including a modulator being operable to modulate pump laser radiation including a train of radiation pulses to provide modulated pump laser radiation, the modulation being such to selectively provide a burst of the pulses; and a hollow-core photonic crystal fiber being operable to receive the modulated pump laser radiation and excite a working medium contained within the hollow-core photonic crystal fiber so as to generate supercontinuum radiation.

An optical resonator system comprises an optical resonator (30) and means (32, 42, 44) for coupling into the resonator counterpropagating waves at total intensities such as to produce a non-linear interaction between the first and second waves whereby to break the symmetry to establish different resonant frequencies between the first and second counterpropagating waves whereby to produce different optical effects in the opposite directions. A common light source, e.g. a laser 32, is employed with an amplifier 40 and a modulator 50, or different light sources can be employed.

In the examples provided herein, an optical logic gate includes multiple couplers, where no more than two types of couplers are used in the optical logic gate, and further wherein the two types of couplers consist of: a 3-dB coupler and a weak coupler with a given transmission-to-reflection ratio. The optical logic gate also includes a first resonator, wherein the first resonator comprises a photonic crystal resonator or a nonlinear ring resonator, wherein in operation, the first resonator has a dedicated continuous wave input to bias a complex amplitude of a total field input to the first resonator such that the total field input is either above or below a nonlinear switching threshold of the first resonator, where the optical logic gate is an integrated photonic circuit.

The present invention introduces a laser ablation arrangement and a corresponding method for PLD applications, where circular scanning patterns are utilized to achieve high scanning velocities on target surfaces for efficient coating process. The arrangement allows for flexible positioning of targets and scan lines in order to optimize coating uniformity on large surface areas as well as high duty cycle for scanning. These features are all essential for achieving efficient industrial coating processes. Fast optical switching and synchronized rotation of scanning mirrors enable efficient distribution of laser energy along long scan line paths on target surfaces.

In the examples provided herein, an optical logic gate includes multiple couplers, where no more than two types of couplers are used in the optical logic gate, and further wherein the two types of couplers consist of: a 3-dB coupler and a weak coupler with a given transmission-to-reflection ratio. The optical logic gate also includes a first resonator, wherein the first resonator comprises a photonic crystal resonator or a nonlinear ring resonator, wherein in operation, the first resonator has a dedicated continuous wave input to bias a complex amplitude of a total field input to the first resonator such that the total field input is either above or below a nonlinear switching threshold of the first resonator, where the optical logic gate is an integrated photonic circuit.

Techniques are described for using confinement structures and/or pattern gratings to reduce or prevent the wicking of sealant polymer (e.g., glue) into the optically active areas of a multi-layered optical assembly. A multi-layered optical structure may include multiple layers of substrate imprinted with waveguide grating patterns. The multiple layers may be secured using an edge adhesive, such as a resin, epoxy, glue, and so forth. A confinement structure such as an edge pattern may be imprinted along the edge of each layer to control and confine the capillary flow of the edge adhesive and prevent the edge adhesive from wicking into the functional waveguide grating patterns of the layers. Moreover, the edge adhesive may be carbon doped or otherwise blackened to reduce the reflection of light off the edge back into the interior of the layer, thus improving the optical function of the assembly.

A single photon detector (SPD) includes a resonator to store probe photons at a probe wavelength and an absorber disposed in the resonator to absorb a signal photon at a signal wavelength. The absorber is also substantially transparent to the probe photons. In the absence of the signal photon, the resonator is on resonance with the probe photons, thereby confining the probe photons within the resonator. Absorption of the signal photon by the absorber disturbs the resonant condition of the resonator, causing the resonator to release multiple probe photons. A photodetector (PD) then detects these multiple probe photons to determine the presence of the signal photon.

A method for generating ultrashort pulses includes directing a master beam having ultrashort pulses and at least one slave beam through an optical gate material. The intensity of the slave beam upstream of the optical gate material is lower than that of the master beam upstream of the optical gate material. The optical gate material and the pulses of the master beam are chosen to induce a Kerr effect when the master beam passes through the optical gate material, the Kerr effect producing a modulation of the phase of the slave beam in association with pulses of the master beam when the slave beam passes through the optical gate material. The modulation of the phase of the slave beam is transformed into a modulation of the amplitude thereof using a complementary optical device to generate a slave beam downstream of the optical gate material having ultrashort pulses.

A wideband ultra-high refractive index mesoscopic crystal structure including: a first layer with high-conductivity unit bodies arranged in a matrix form, and a low-conductivity material disposed between the high-conductivity unit bodies; a second layer with high-conductivity unit bodies arranged in a matrix form, and a low-conductivity material disposed between the high-conductivity unit bodies; a first shield layer existing between the first and second layers and made of a low-conductivity material; and a second shield layer made of a low-conductivity material disposed on a side of the second layer such that the second layer is disposed between the first shield layer and the second shield layer, wherein the high-conductivity unit bodies in the first layer overlap the high-conductivity unit bodies arranged in the second layer, and wherein the first layer, the first shield layer, the second layer, and the second shield layer are sequentially stacked one or more times.

Embodiments are directed to a (quasi) one-dimensional photonic crystal cavity. This cavity comprises a set of aligned pillars, where the pillars are embedded in a cladding. At least one of the pillars has a sandwich structure, wherein a layer of nonlinear optical material is between two layers of materials having, each, a refractive index that is higher than the refractive index of the nonlinear optical material. Embodiments can further include an all-optical modulator or an all-optical transistor, comprising a photonic crystal such as described above. Finally, embodiments are further directed to methods for modulating an optical signal, using such a photonic crystal cavity.