This disclosure is directed at a method and device capable of producing polarization entangled photon pairs and accomplishing polarization insensitive wavelength conversion. The device includes a double displacement interferometer, the interferometer of which contains an input beam displacing section including a plurality of orthogonally oriented optical beam displacing elements; a wavelength conversion section including a plurality of orthogonally oriented non-linear optical wavelength converters; an output beam recombination section including a plurality of orthogonally oriented optical beam displacing elements.

According to various embodiments, an all-optical thresholder device is disclosed. The all-optical thresholder device includes a Mach-Zehnder interferometer (MZI) coupled to a Mach-Zehnder coupler (MZC). The MZI includes at least one microring resonator (MRR) and a first tunable element, where the MRR further includes a second tunable element. The MZC includes a third tunable element. The first, second, and third tunable elements are configured to control biases of the all-optical thresholder device to achieve a desired power transfer function.

A system and method is provided for imaging and/or spectroscopy involving generation of a first signal field and a first idler field, illumination of the object with the first idler field, generation of second signal field and a second idler field, combination of the first and second idler fields, such that the two fields are indistinguishable, combination of the first and second signal fields, such that the two fields interfere, first measurement of the interfered signal field by a detection means, one or more additional measurements of the interfered signal field, wherein for each additional measurement a different phase shift is generated in the setup, and wherein all measurements are carried out within the stability time of the setup, and calculation of a phase function.

Systems and methods for activation in an optical circuit in accordance with embodiments of the invention are illustrated. One embodiment includes an optical activation circuit, wherein the circuit comprises a directional coupler, an optical-to-electrical conversion circuit, a time delay element, a nonlinear signal conditioner, and a phase shifter. The directional coupler receives an optical input and provides a first portion to the optical-to-electrical conversion circuit and a second portion to the time delay element, the time delay element provides a delayed signal to the phase shifter, and the optical-to-electrical conversion circuit converts an optical signal from the directional coupler to an electrical signal used to activate the phase shifter to shift the phase of the delayed signal.

Reconfigurable nonlinear frequency conversion waveguide chip based on Mach-Zehnder interferometer coupled micro-ring, the method is based on the integration of waveguide components of phase-adjustable Mach-Zehnder interferometers (MZI) and micro-ring resonators. The chip is illustrated by FIG. 1. The MZI couples light and photons into and output of the micro-ring resonator and controls the micorings' quality factor thus optimize the nonlinear frequency conversion processes inside the ring by the phase-modulator inside the MZI. The micro-ring resonator enables the nonlinear optical generation of new frequency light beams and quantum light sources based on the second-order or third-order nonlinear optical process. Other optical waveguide components in region I and III of FIG. 1 are linear optical circuits for power splitting of pump beams and post-process of generated light beams or photons.

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.

Systems, devices, and methods are provided for all-optical reconfigurable activation devices for realizing various activations functions having normalized output power. The device and systems disclosed herein include an interferometer comprising a first branch formed of a first waveguide and a second branch formed of a second waveguide. A resonator cavity is coupled to the second first waveguide and at least one phase-shift mechanism is coupled to one of the second waveguide and the resonator cavity. The at least one phase-shift mechanism is configured to control biases of the interferometer to achieve a desired activation function at an output of the interferometer, and an optical amplification mechanism is coupled to the output of the interferometer and configured to add optical gain to the desired activation function.

Single-shot transient optical signals are recorded in a time regime of picoseconds to nanosecond. An auxiliary pump beam is crossed through the signal to sample a diagonal slice of space-time, analogous to a rolling shutter. The slice is then imaged onto an ordinary camera, where the recorded spatial trace is a direct representation of the time content of the signal. The pump samples the signal by optically exciting carriers that modify the refractive index in a conventional semiconductor wafer. Through use of birefringent retarders surrounding the wafer, the integrating response of the rapidly excited but persistent carriers is differentiated by probing with two polarization-encoded time-staggered signal replicas that are recombined to interfere destructively.

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.

Systems, devices, and methods are provided for all-optical reconfigurable activation devices for realizing various activations functions having normalized output power. The device and systems disclosed herein include an interferometer comprising a first branch formed of a first waveguide and a second branch formed of a second waveguide. A resonator cavity is coupled to the second first waveguide and at least one phase-shift mechanism is coupled to one of the second waveguide and the resonator cavity. The at least one phase-shift mechanism is configured to control biases of the interferometer to achieve a desired activation function at an output of the interferometer, and an optical amplification mechanism is coupled to the output of the interferometer and configured to add optical gain to the desired activation function.