A quantum communication system that includes a multiphoton entanglement generator, a plurality of photon detector units, and a plurality of optical fiber links. The plurality of photon detector units include a first photon detector unit and a second photon detector unit. The multiphoton entanglement generator is structurally configured to output more than two entangled photons. The plurality of optical fiber links comprise a first optical fiber link optically coupled to the multiphoton entanglement generator and disposed between the multiphoton entanglement generator and the first photon detector unit. The plurality of optical fiber links comprise a second optical fiber link optically coupled to the multiphoton entanglement generator and disposed between the multiphoton entanglement generator and the second photon detector unit. Further, at least one of the plurality of optical fiber links has a core, a cladding, and a scattering region having a plurality of scattering structures.

An optical neural network is constructed based on photonic integrated circuits to perform neuromorphic computing. In the optical neural network, matrix multiplication is implemented using one or more optical interference units, which can apply an arbitrary weighting matrix multiplication to an array of input optical signals. Nonlinear activation is realized by an optical nonlinearity unit, which can be based on nonlinear optical effects, such as saturable absorption. These calculations are implemented optically, thereby resulting in high calculation speeds and low power consumption in the optical neural network.

Techniques are described for imaging a sample where the techniques include acquiring a raster scan image of the sample, providing light from a light source, directing the light into a plurality of different light beam paths at different times, providing light in each of the plurality of light beam paths through an objective lens to the sample, and providing light in each of the plurality of beams to different locations within the sample. Fluorescence emission light from the sample is detected in response to excitation by light in each of the plurality of light beam paths, where the detected fluorescence emission light corresponds to fluorescence intensity projections of the sample with low mutual coherence, and an image of the sample is generated based on the detected fluorescence emission light and based on the raster scan image.

A system is provided for producing an output photon having a predefined frequency. A pump module produces a plurality of pump fields at a plurality of pump frequencies. A photon pair source module generates frequency-correlated photon pairs. A detector module generates a heralding signal subsequent to detecting a first photon of a photon pair, the heralding signal indicative of a frequency of the second photon of the pair. A non-linear photonic element is arranged to (1) receive the heralded second photon and a complementary selected pump field, and (2) to produce an output photon having the predefined frequency. A pump field selector is configured to (1) receive a heralding signal and (2) select, based on the received heralding signal, a pump field of the plurality of pump fields for provision to the non-linear element. Methods, controllers and computer-readable media are also described herein.

A system is disclosed for producing an output photon having a predefined frequency. The system comprises a frequency comb generator for generating a frequency comb. The system further comprises a frequency comb mode selector configured to: receive a heralding signal representative of the detection of a first photon of a frequency-correlated photon pair, the heralding signal indicative of a frequency of the heralded second photon of the frequency-correlated photon pair; and select, based on the received heralding signal, a comb spectral mode of the frequency comb. The system further comprises a non-linear photonic element configured to receive the heralded second photon and the selected comb spectral mode and produce an output photon having the predefined frequency based on the frequency of the heralded second photon and the selected comb spectral mode. Methods, controllers and computer-readable media are also described herein.

A system for generating clock signals for a photonic quantum computing system includes a pump photon source configured to generate a plurality of pump photon pulses at a first repetition rate, a waveguide optically coupled to the pump photon source, and a photon-pair source optically coupled to the first waveguide. The system also includes a photodetector optically coupled to the photon-pair source and configured to generate a plurality of electrical pulses in response to detection of at least a portion of the plurality of pump photon pulses at the first repetition rate and a clock generator coupled to the photodetector and configured to convert the plurality of electrical pulses into a plurality of clock signals at the first repetition rate.

An optical neural network is constructed based on photonic integrated circuits to perform neuromorphic computing. In the optical neural network, matrix multiplication is implemented using one or more optical interference units, which can apply an arbitrary weighting matrix multiplication to an array of input optical signals. Nonlinear activation is realized by an optical nonlinearity unit, which can be based on nonlinear optical effects, such as saturable absorption. These calculations are implemented optically, thereby resulting in high calculation speeds and low power consumption in the optical neural network.

A coherent photon analog-to-digital conversion device comprising an optical clock oscillation source, a sampled signal source, a photon sampling gate, a photoelectric detection module, an electrical sampling module, a phase detection module, a loop filter, and signal feedback links. By adjusting the optical clock oscillating source or the sampled signal source, the invention makes the two highly coherent, thereby reducing the clock jitter and greatly improving the sampling precision. It is very important for improving the performance of microwave photon systems that require high time accuracy and high sampling accuracy, such as microwave photon radar and optical communication systems.

An imaging system comprises a light source generating a pump beam, and an optical coupling system for receiving an input beam of infrared light from a scene and combining the input beam with the pump beam, wherein an intensity of the pump beam is higher than an intensity of the input beam. The imaging system further comprises a crystal configured for adiabatically mixing the beams and providing an output beam having a frequency which is a sum of frequencies of the input and pump beams, and a visible, near-infrared or ultraviolet light imager configured for collecting and to spectrally resolving the output beam.

Wavelength-tunable source of pulsed laser radiation for VIS-NIR spectroscopy which consists of a pump source (1) forming bursts of picosecond pulses of high pulse repetition rate, and a synchronously pumped optical parametric oscillator (2). The pump source (1) comprises a solid-state regenerative amplifier (31) having one or two electro-optical switches (32,33) inside its resonator (44). The switches create partial transmission of the resonator for a time interval longer than a resonator roundtrip time, and eject a part of energy of a pulse circulating inside. Bursts of 5-10 ns duration are formed, which are filled with high peak power picosecond pulses. Pulse repetition rate of the order of GHz of pump pulses allows the construction of a compact optical parametric oscillator. The whole set of parameters ensures high energy efficiency, stability and an ability to provide output pulse bursts repeating at up to 10 kHz repetition rate.