Abstract: A method includes calculating a plurality of permutation matrices of an input matrix that characterizes a linear transformation of a plurality of input states. The method also includes determining a plurality of settings of an optical circuit based on the plurality of permutation matrices. Each setting in the plurality of settings is associated with an electric power, from a plurality of electric powers, consumed by the optical circuit. The method also includes determining a selected setting of the optical circuit based on the electric power from the plurality of electric powers and consumed by the optical circuit at each setting from the plurality of settings associated with the electric power. The method further includes implementing the selected setting on the optical circuit to perform the linear transformation of the plurality of input states.

Abstract: A sensor system is based on diamonds with a high density of NV centers. The description includes a) methods for producing the necessary diamonds of high NV center density, b) characteristics of such diamonds, c) sensing elements for utilizing the fluorescence radiation of such diamonds, d) sensing elements for utilizing the photocurrent of such diamonds, e) systems for evaluating these quantities, f) reduced noise systems for evaluating these systems, g) enclosures for using such systems in automatic placement equipment, g) methods for testing these systems, and h) a musical instrument as an example of an ultimate application of all these devices and methods.

Abstract: A quantum communication system for encrypting communication includes a processor configured to receive an encryption request from a mobile device. The mobile device determines a first encryption key from the mobile device. A quantum random number generator generates a second encryption key using quantum mechanics. The processor transmits the second encryption key to the mobile device. The mobile device implements a digital XOR logic gate configured to perform an XOR operation on the first encryption key and the second encryption key to generate a third encryption key.

Abstract: An apparatus includes a light source to provide a plurality of input optical modes in a squeezed state. The apparatus also includes a network of interconnected reconfigurable beam splitters (RBSs) configured to perform a unitary transformation of the plurality of input optical modes to generate a plurality of output optical modes. An array of photon counting detectors is in optical communication with the network of interconnected RBSs and configured to measure the number of photons in each mode of the plurality of the output optical modes after the unitary transformation. The apparatus also includes a controller operatively coupled to the light source and the network of interconnected RBSs. The controller is configured to control at least one of the squeezing factor of the squeezed state of light, the angle of the unitary transformation, or the phase of the unitary transformation.

Abstract: Generally, a polymer nanomaterial encapsulation system useful in the production of polymer encapsulated nanoparticles comprised of a hydrophobic nanoparticle encapsulated in the hydrophobic region of the polymer with the external hydrophilic region of the polymer ensuring water-solubility and affording a functional group which can be utilized for the production of nanoparticle conjugates. Specifically, particular embodiments include a polymer nanoparticle structure including one or more of: a quantum dot and/or a superparamagnetic iron oxide nanoparticle and/or an upconverting nanoparticle, encapsulated in polystyrene-b-polyethylene glycol amine for the production of antibody conjugates useful in the capture of cellular targets.

Abstract: The present application discloses an integrated self-coherent receiving optical chip based on round-trip delay interferometers, including a first beam splitter, a multi-port circulator array, a first round-trip delay interferometer and a second round-trip delay interferometer integrated on a same substrate, wherein the first beam splitter is connected to the multi-port circulator array, and the multi-port circulator array is connected to the first round-trip delay interferometer and the second round-trip delay interferometer, respectively.

Abstract: Disclosed is an eddy current flaw detection system based on a NV (nitrogen-vacancy) color center quantum sensing technology, relating to the technical field of quantum sensing. The system includes a laser transceiver processing unit, a quantum sensor, an excitation coil, a power supply unit, a microwave coil, and a microwave unit. The diamond NV color center precision measurement technology and the eddy current nondestructive flaw detection technology are combined in accordance with the present disclosure. Compared with the traditional technology, the remarkable performance of the diamond NV color center can improve the accuracy of eddy current nondestructive flaw detection and achieve the accurate detection of fine crack defects. Meanwhile, a detection method for an alternating current magnetic field is designed according to the characteristics of the eddy current nondestructive flaw detection.

Abstract: Disclosed is a self-coherent receiver based on polarization-independent delay interferometers, relating to a technical field of optical communication, including a first beam splitter, a first circulator, a second circulator, a first polarization-independent delay interferometer, a second polarization-independent delay interferometer, a first balanced detector, a second balanced detector and an electrical signal processing module.

Abstract: An apparatus includes an optical circuit having at least one reconfigurable beamsplitter and is configured to receive a plurality of input optical modes in a Gaussian state and generate a plurality of output optical modes. The apparatus also includes at least one detector optically coupled with the optical circuit and configured to perform a non-Gaussian measurement of a first output optical mode from the plurality of output optical modes. The non-Gaussian measurement of the first output optical mode is configured to cause a second output optical mode from the plurality of output optical modes to be in a first non-Gaussian state. The apparatus also includes a controller operatively coupled to the optical circuit and configured to change a setting of the at least one reconfigurable beamsplitter to cause the second output optical mode from the plurality of output optical modes to be in a second non-Gaussian state.

Abstract: The application discloses a polarization independent DQPSK demodulation integrated optical chip, which comprises a first beam splitter, a first polarization beam splitter rotator, a second beam splitter, a third beam splitter, a first quarter-wave plate, a first delayed optical waveguide, and a second polarization beam splitter rotator that are integrated on a same substrate.

Abstract: Some embodiments in the present disclosure relate to an apparatus and methods to excite a trapped ion. A first laser beam and a second laser beam pass through at least one common lens of an objective. The two laser beams are focused by said objective at the position of the trapped ion. A moving standing wave is generated at the position of the trapped ion, which induces a force on the trapped ion. Two ions may be entangled by generating such moving standing wave at the respective positions of both of said ions.

Abstract: An apparatus includes an optical circuit having at least one reconfigurable beamsplitter and is configured to receive a plurality of input optical modes in a Gaussian state and generate a plurality of output optical modes. The apparatus also includes at least one detector optically coupled with the optical circuit and configured to perform a non-Gaussian measurement of a first output optical mode from the plurality of output optical modes. The non-Gaussian measurement of the first output optical mode is configured to cause a second output optical mode from the plurality of output optical modes to be in a first non-Gaussian state. The apparatus also includes a controller operatively coupled to the optical circuit and configured to change a setting of the at least one reconfigurable beamsplitter to cause the second output optical mode from the plurality of output optical modes to be in a second non-Gaussian state.

Abstract: A scalar magnetometer includes a sensor element, a circuit carrier, a pump radiation source, a radiation receiver and evaluation means. The pump radiation source emits pump radiation. The sensor element preferably includes one or more NV centers in diamond as paramagnetic centers. This paramagnetic center emits fluorescence radiation when irradiated with pump radiation. The radiation receiver converts a intensity signal of the fluorescence radiation into a receiver output signal. The evaluation means detects and/or stores and/or transmits the value of the receiver output signal. The material of the circuit carrier is preferably transparent for the pump radiation in the radiation path between pump radiation source and sensor element and transparent for the fluorescence radiation in the radiation path between sensor element and radiation receiver. The components sensor element, pump radiation source, radiation receiver and evaluation means are preferably mechanically attached to the circuit carrier .

Abstract: Provided are a laser device and a method of transforming laser spectrum, which provide a laser frequency stabilization and significant narrowing a laser spectrum. A laser device includes at least one multiple longitudinal mode laser (L) for generating a laser light having a spectrum of multiple longitudinal modes; at least one high quality factor (high-Q) microresonator (M) optically feedback coupled to the at least one multiple longitudinal mode laser (L); and a tuner (TU) for tuning the spectrum of multiple longitudinal modes of the laser light. The laser device is configured to output an output laser light having an output spectrum with at least one dominant longitudinal laser mode each at a reduced linewidth of the dominant longitudinal laser mode. The laser device allows increasing an emission power of a narrow linewidth lasing without an additional amplification while keeping a compact size of a device with a limited number of optical elements.

Abstract: A system for scalable, fault-tolerant photonic quantum computing includes multiple optical circuits, multiple photon number resolving detectors (PNRs), a multiplexer, and an integrated circuit (IC). During operation, the optical circuits generate output states via Gaussian Boson sampling (GBS), and the PNRs generate qubit clusters based on the output states. The multiplexer multiplexes the qubit clusters and replaces empty modes with squeezed vacuum states, to generate multiple hybrid resource states. The IC stitches together the hybrid resource states into a higher-dimensional cluster state that includes states for fault-tolerant quantum computation.

Abstract: A method includes receiving a representation of an N-mode interferometer and a representation of at least one imperfection associated with the N-mode interferometer at a processor, N being a positive integer value. The processor identifies multiple two-mode interferometers and multiple phases based on the representation of the N-mode interferometer and the representation of the at least one imperfection. The multiple two-mode interferometers and the multiple phases are configured to apply a unitary transformation to an input signal. The method also includes sending a signal to cause at least one of storage or display of a representation of the multiple two-mode interferometers and a representation of the multiple phases.

Abstract: The present disclosure relates to the technical field of current sensors, and provides a fiber-optic current transformer based on nitrogen-vacancy (NV) centers in diamond, and a measurement method. The fiber-optic current transformer based on NV centers in diamond includes a device for laser light excitation and reflected light reception and analysis, a diamond NV center probe, a magnetic concentrator, and a microwave excitation device. The fiber-optic current transformer based on NV centers in diamond includes three measurement methods: an all-optical measurement method, a non-all-optical measurement method, and a measurement method combining the all-optical measurement method and the non-all-optical measurement method. A sensor in the present disclosure has advantages of a simple structure, strong practicability, resistance to external interference, and strong robustness.

Abstract: Protected quantum dots are protected from degradation, particularly in aqueous environments, The system comprises quantum dots, hydrophobic core, and hydrophilic shell. The quantum dots are entrapped in and protected by the hydrophobic core. The core polymer is covalently bonded to a hydrophilic shell polymer or protein. Quantum yield is better maintained than for non-encapsulated quantum dots in an aqueous environment. Optionally, ligands are attached to the hydrophilic shell to target delivery of the protected quantum dots, In an alternative embodiment, quantum dots are entrapped in the hydrophilic shell, or in both the shell and the core.

Abstract: A miniaturized PPKTP crystal-based entanglement source system using multi-mode reception is provided, which includes a pump light source, a pump light transmission module, an entanglement device, a first collection device, and a second collection device. In the entanglement source system, entangled lights are received by using multi-mode optical fibers, and an entangled light processing scheme of combining a temporal filtering technology and a spatial filtering technology is applied into a collecting device at one side of the entanglement source system, to form asymmetric device structures in the entanglement source system, to enable multi-mode reception.

Abstract: An apparatus includes a light source to provide a plurality of input optical modes in a squeezed state. The apparatus also includes a network of interconnected reconfigurable beam splitters (RBSs) configured to perform a unitary transformation of the plurality of input optical modes to generate a plurality of output optical modes. An array of photon counting detectors is in optical communication with the network of interconnected RBSs and configured to measure the number of photons in each mode of the plurality of the output optical modes after the unitary transformation. The apparatus also includes a controller operatively coupled to the light source and the network of interconnected RBSs. The controller is configured to control at least one of the squeezing factor of the squeezed state of light, the angle of the unitary transformation, or the phase of the unitary transformation.