4901 results about "Quantum electrodynamics" patented technology

The technology relates to enhancing performance of quantum sensor operation in a noisy environment. Quantum neural networks are used to pre- and post-process analog signals to which qubits of a quantum sensor are exposed. Intra-processing using additional quantum neural networks may also be employed. This approach filters out noise from both the input analog signal and the system itself to achieve a very high signal to noise ratio. This permits the system to detect induced dynamics associated during exposure of the qubits to the analog signals. This enables the quantum sensor to sense a change in a state of a system under test, which can be beneficial for areas such as imaging, magnetometry, sensing electric fields, optomechanical sensors, quantum radar and other areas where enhanced signal to noise ratios are desired.

In a general aspect, a quantum program can be automatically synthesized or compiled. In some implementations, a discretized state space is obtained. The discretized state space includes a plurality of states for one or more qubits of a quantum processor. A discrete action space is obtained. The discrete action space includes a plurality of unitary operations for the one or more qubits of the quantum processor. A policy that uses the discretized state space and the discrete action space to generate quantum programs for quantum state preparation is defined. A dynamic programming process is used to improve the policy. An initial state and a target state of the one or more qubits is identified. The policy is used to generate a quantum program to produce the target state from the initial state. The quantum program include a subset of the unitary operations in the discrete action space.

The invention discloses a nut defect detection method based on X-ray imaging, and particularly relates to the field of X-ray nut material internal defect imaging, which comprises the following steps: generating and adjusting an initial light beam of X-rays through a synchronous radiation source, and constructing uniform irradiation field data for nut material detection; acquiring angle scattering light intensity matrix data based on the uniform irradiation field data; and performing phase inversion and sparse constraint optimization on the angle scattering light intensity matrix data to generate electron cloud density optimization distribution data, and constructing density connectivity relation graph data based on the electron cloud density optimization distribution data. By introducing a detection principle of combining high-coherence X-ray scattering imaging based on a synchronous radiation source and electron cloud density disturbance analysis, lossless identification of an early microcosmic physical deterioration region in a nut is realized; the problem that an existing method based on absorption imaging is insufficient in defect detection capacity under the background of weak density gradient and homogeneous component is solved.

The invention relates to the technical field of quantum computing, and provides a polariton quantum computing simulation method and related device.The method comprises the steps that parameterized quantum circuits are generated based on micromodels used for describing polaritons for all to-be-computed excitation states respectively, and the parameterized quantum circuits are generated based on initial Hamiltonian of polaritons in a ground state; the target Hamiltonian amount of the polariton in the current excitation state is obtained, then the value of each parameter is adjusted at least once, and the target energy of the corresponding excitation state is obtained. In the primary adjustment process, parameter updating is carried out on the quantum circuit, a reference quantum state of the corresponding excitation state is obtained by utilizing the updated quantum circuit, reference energy of the corresponding excitation state is obtained based on the reference quantum state and in combination with the target Hamiltonian, and then when a set convergence condition is met, the target Hamiltonian is obtained. And taking the reference energy as target energy of the corresponding excited state. The polaritons are simulated through the quantum computer, and the simulation efficiency is improved.

A quantum computing service provides a quantum algorithm development kit that enables a customer to define a quantum task, a quantum algorithm, or a quantum circuit using an intermediate representation. The quantum computing service is then configured to automatically translate the quantum task, quantum algorithm, or quantum circuit into a specific representation specific to a particular quantum computing technology selected by the customer to be used to execute the customer's quantum task, quantum algorithm, or quantum circuit.

The invention discloses a point light source electron accelerator which comprises a sealing box body, a cathode, a laser emitter, a reflecting cover, a grid plate and a mounting plate, the mounting plate is erected in the sealing box body, a mounting hole is formed in the mounting plate, the cathode is mounted in the mounting hole, and the laser emitter is arranged in the sealing box body. The reflecting cover is arranged at the top of the mounting hole; the reflecting cover is a semi-spherical surface, a laser through hole is formed in the top of the semi-spherical surface, and the laser through hole is coaxial with the cathode; the transmitting end of the laser transmitter is aligned with the cathode; the grid plate is mounted below the mounting plate and is aligned with the mounting holes; and an electron outlet is formed below the grid plate. The invention provides a point light source electron accelerator, and the point light source electron accelerator provides a light and miniaturized electron accelerator design, so that the application field of the accelerator is wider.

The invention provides a nonlinear data generation and processing method based on light quantum and a light quantum computer, and the method comprises the steps: obtaining a nonlinear function and attribute information of a nonlinear layer; according to the frequency spectrum number and the attribute information of the nonlinear function, constructing an initial light quantum circuit; measuring the initial light quantum circuit, and determining a target function corresponding to the initial light quantum circuit according to a measurement result; loss information of the target function is determined, whether the initial light quantum circuit is applied or not is determined according to the loss information, and if yes, the initial light quantum circuit serves as a target light quantum circuit; and performing operation on input data of the nonlinear layer based on the target light quantum circuit. According to the method, the low-energy-consumption characteristic of photon calculation, the nonlinear characteristic of light quantum calculation and the general programmable capability of electronic calculation can be fused, and high-energy-efficiency calculation can be carried out on input data of a nonlinear layer. In addition, the method also has the advantages that the complexity of a quantum circuit is smaller, and the participation of a nonlinear optical device is not needed.

A multirail-encoded qubit can be implemented using a quantum system having a state space that includes a number M of distinct modes, where M is an integer greater than 2. The M modes are logically partitioned into two disjoint subsets (or “bands”), with each mode assigned to exactly one of the bands. The multirail encoding is defined such that a state in which any one of the modes in the first band is occupied and all modes in the second band are unoccupied maps to a logical 0 state of the qubit, and a state in which any one of the modes in the second band is occupied and all modes of the first band are unoccupied maps to a logical 1 state. Systems and methods for generating, measuring, and operating on multirail-encoded qubits are disclosed.

The invention discloses a defect-free neutral atom array preparation method and system based on dynamic optical tweezers rearrangement, and belongs to the technical field of quantum computing. The invention discloses a defect-free neutral atom array preparation method and system based on dynamic optical tweezers rearrangement. A static optical tweezers array is generated through a spatial light modulator to capture initial atoms, an optimal rearrangement path is planned by adopting a Hungary algorithm, and dynamic optical tweezers are generated through an acousto-optic deflector to implement atom grabbing, moving and releasing operation. According to the method, a weighted Gerchberg-Saxton algorithm is innovatively combined with real-time image feedback, so that the precise rearrangement of the atom array is realized. Important experimental technical support is provided for quantum calculation and simulation, and the application progress of the neutral atom array in the fields of quantum error correction, fault-tolerant quantum calculation, quantum simulation and the like is effectively promoted.

A method for secure quantum communication includes generating a photon. The method includes modulating at least two quantum state dimensions selected from the group consisting of orbital angular momentum (OAM), polarization, and phase of the photon to form a composite quantum state. The method includes directing the photon to an emission point on a helical structure having a defined spatial coordinate corresponding to classical data. The method includes emitting the photon from the emission point into a quantum channel. The composite quantum state and spatial coordinate together encode secure information.

An electron-optical projection device for projecting a plurality of charged particle beams towards a sample, the device comprising a stack of plates comprising beam directing elements configured to project the plurality of charged particle beams towards a sample location on the sample, wherein at least one plate of the stack comprises a planar optical member configured to direct stimulation light towards the sample location so that the stimulation light is coincident with the plurality of charged particle beams, desirably coincident with the paths of the plurality of charged particle beams towards the sample location, desirably in the at least one plate comprising an optical member is defined a plurality of apertures for respective paths of a plurality charged particle beams.

A control system for a network of quantum systems operates the network to perform quantum informatics processing. The control system includes an entanglement scheduler configured to identify operations for which entanglement of two or more of the quantum systems is desired, identify plural potential entanglement attempts for generating the entanglement; and schedule at least some of the potential entanglement attempts to be performed to generate the entanglement for at least one of the operations. The entanglement scheduler may use direct entanglement, entanglement swapping and / or quantum teleportation approaches to generate the entanglement. The entanglement scheduler may schedule probabilistic entanglement attempts based at least in part on the probability of success of the entanglement attempts. The entanglement scheduler may generate entanglement to support plural branches of a quantum informatics process and / or to respond to events occurring while the quantum informatics process is executing.

This invention provides a Rydberg-atom based electromagnetic field detector array comprising a plurality of Rydberg-atom based electromagnetic field detectors, wherein each Rydberg-atom based electromagnetic field detector is divided into a plurality of units, each unit of the plurality of units being either: a variable transparency unit configured to vary its transparency by the Electromagnetically Induced Transparency, EIT, effect and further vary its transparency in response to an incident electromagnetic field, or a separator unit, wherein a sequence of one or more variable transparency units and one or more separator units of the plurality of units for a Rydberg-atom based electromagnetic field detector uniquely identifies that Rydberg-atom based electromagnetic field detector in the Rydberg-atom based electromagnetic field detector array.

Development of technologies for effectively suppressing edge localized modes (ELM), maintaining core plasma stability, controlling plasma rotation, adjusting edge transport barriers, achieving smooth transitions between different plasma regimes, minimizing error magnetic fields, sustaining plasma for long periods, stabilizing fusion power, controlling plasma impurities, and optimizing plasma-wall interactions simultaneously in tokamak fusion reactors. [Solution] We provide an adaptive edge-localized 3D magnetic field control system that organically links a real-time plasma state monitoring system, a 3D magnetic field response prediction model, a flexible 3D coil system, an adaptive control algorithm, a plasma regime transition management system, an integrated control interface, a high-precision magnetic diagnostic system, a fusion power control system, a plasma impurity control system, and a plasma-wall interaction optimization system.

A LSP broadband light source is disclosed. The light source may include a gas containment structure. The light source may include multiple jet nozzles, wherein the jet nozzles are configured to generate supersonic gas jets and direct the supersonic gas jets to collide within the gas containment structure to form a localized high-pressure region at the collision point. The light source may include a primary laser pump source, wherein the primary laser pump source is configured to direct a primary pump beam to a localized high-pressure region formed at the collision point. The light source may include a pulsed-assisting laser source, wherein the pulsed-assisting laser source is configured to direct a pulsed-assisting beam to the localized high-pressure region at the collision point. The light source may include a light collector element configured to collect broadband light emitted from the plasma.

A charge detection mass spectrometer includes an ion trap configured to store ions therein and to release stored ions therefrom, and an electrostatic linear ion trap (ELIT) array, in the form of at least two ELITs or ELIT regions each spaced apart from the ion trap, each ELIT or ELIT region including first and second ion mirrors and a charge detection cylinder positioned therebetween. The ion trap is controlled to release at least some of the stored ions to travel toward and into each of the ELITs or ELIT regions, and the first and second ion mirrors of each of the ELITs or ELIT regions is controlled in a manner which traps one or more ions traveling therein and causes the trapped ion(s) to oscillate back and forth between the first and second ion mirrors each time passing through and inducing a corresponding charge on the charge detection cylinder.

The invention discloses a mixed gas absorption spectrum analysis method and system based on variational mode decomposition, specific laser is injected into an optical resonant cavity unit, and a detector unit continuously monitors the light intensity change and records a light intensity attenuation signal; pre-processing the recorded light intensity attenuation signal; carrying out VMD decomposition on the preprocessed ring-down signal to obtain a plurality of IMF components, respectively introducing CO2 and CO gases with known concentrations into the optical resonance unit, and recording spectral data of each single gas component; calculating the similarity and contribution degree of each IMF component, and setting a weight combination to form a joint score; the gas with the highest joint score is selected, the score is compared with an adaptive threshold value, and when the score is higher than the adaptive threshold value, the IMF component is marked as the characteristic component of the corresponding gas; and finally, gathering and outputting the marked IMF components according to gas types to obtain characteristic signals of the gases, thereby realizing multi-component gas separation in the mixed gas absorption spectrum.

Techniques are described for implementing a class of multimode bosonic codes that protect against errors within an ancilla qubit coupled to a bosonic system, that can be realized experimentally. A logical qubit state is represented by the states of multiple different modes of one or more bosonic systems, which may include multiple modes of a single bosonic system and / or single modes from multiple bosonic systems. Techniques for correcting errors are also described. In particular, a series of operations are described that autonomously detect and correct errors by repeatedly performing a sequence of operations that are each applied to the multiple bosonic modes and / or to the ancilla qubit that is coupled to each of the bosonic modes. The codes allow ancilla errors to propagate to the modes of the bosonic system as correctable errors, where they can be corrected, instead of presenting as logical errors in the ancilla qubit.

Provided are computer-implemented methods and quantum computing systems for preparing computational states representing quantum states of a physical system, including performing a computational evolution of the state and then determining physical properties of the system using the time-evolved computational state. Hamiltonian dynamics of observables are computed on a quantum computer to provide information about the physical system represented by the Hamiltonian. Low energy electronic structure states of a physical system are prepared using adiabatic evolution. The energy of an equilibrium quantum state of a physical system is determined using a time-evolution operator. The energy of an eigenstate of a physical system is indirectly determined by evaluating expectation values of a time-evolution operator averaged across multiple shots for randomly-generated quantum circuits. Example methods enable calculation of the energy of an evolved computational state with chemical accuracy, due to avoiding discretization errors, with a smaller circuit depth than known alternatives.

A method of time-dependent quantum Hamiltonian simulation that is capable of efficiently achieving a target error is described. The time evolution of a time-dependent Hamiltonian describing a physical system is modeled using a Magnus operator that has one or more nested commutators and integrals. The Magnus operator is approximated with a commutator-free operator up to an order n. An error between the commutator-free operator and the Magnus operator as result of the approximation is estimated based at least in part on a simulation step size h. The commutator-free operators may be simulated on a quantum computer via one or more quantum gates for a total simulation time in temporal increments of h, where the step size h has a value such that a simulation error of the simulation is less than or equal to a target error.

The invention relates to the technical field of quantum computing, and provides a linear complexity quantum state preparation method based on tensor decomposition and a quantum circuit construction system.The high-dimensional tensor is decomposed into a series of low-rank core tensors through continuous singular value decomposition, each core tensor in a core tensor sequence is expanded into a unitary matrix, and the unitary matrix is used as a quantum circuit; the unitary matrix sequence is mapped to quantum lines coupled using adjacent qubits, and the quantum lines are run to prepare a target quantum state. Based on this, the line generated by the method can approximately or accurately prepare a target quantum state only by coupling adjacent quantum bits, and is perfectly adaptive to quantum chips of linear or grid topologies such as superconducting and semiconductor quantum dots and the like.

A quantum computing system and methods for performing fusion based quantum computing on encoded qubits. A fusion controller sequentially performs a series of fusion measurements on respective photonic quantum modes of first and second encoded qubits to obtain a respective series of classical measurement results. For respective fusion measurements of the series of fusion measurements, a basis for performing the respective fusion measurement is selected based on classical measurement results of previous fusion measurements. An encoded fusion measurement result is determined based on the classical measurement results, and the encoded fusion measurement result is stored in a memory medium.

The invention discloses an implementation method of a quantum logic gate and a quantum computer system. The method comprises the following steps: preparing a quantum bit to a preset initial quantum state; according to the Hamiltonian corresponding to the quantum logic gate, respectively generating microwave signals corresponding to each segment in the Hamiltonian; the Hamiltonian of the quantum logic gate comprises at least two segments, and the at least two segments are used for enabling quantum bits to generate at least one polarity reversal in evolution; the generated microwave signals corresponding to all the segments are spliced; and applying a spliced microwave signal to the quantum bits in the initial quantum state, so that the quantum bits evolve from the initial quantum state to a target quantum state. According to the invention, the quantum bit can generate at least one polarity change in evolution, partial phase dispersion is offset by using the polarity characteristic of 1 / f noise, decoherence is inhibited, and the fidelity of the single-bit quantum logic gate is further improved.

The present invention relates to a method for calculating an electronic structure of a material by using quantum computing. Particularly, the method of the present invention for calculating an electronic structure of a material performed linking a quantum computer and a classical computer, may comprise the steps of: fragmenting a target molecule into fragments of a plurality of monomers having a predetermined positional relation; performing a first VQE routine for performing a Hamiltonian matrix calculation for the plurality of monomers on the basis of a calculation of electron density for the plurality of monomers, inputting modified electron density, and repeating the first VQE routine performing the Hamiltonian matrix calculation until the modified electron density according to the Hamiltonian matrix by the result of the first VQE routine converges; and performing a second VQE routine for performing a Hamiltonian matrix calculation on one or more dimers consisting of two monomer pairs of the plurality of monomers.

Disclosed herein are an apparatus and method for mutual authentication of quantum entities based on Measurement-Device-Independent Quantum Key Distribution (MDI-QKD). The method may include configuring a quantum input form based on an authentication key shared in advance with a counterpart entity, applying polarization modulation to the configured quantum input form, transmitting the quantum input form to which polarization modulation is applied to a quantum measurement device, and authenticating the counterpart entity by checking whether the counterpart entity configures a quantum input form according to the shared authentication key using a measurement result and information about polarization modulation.

A method, system, and computer program product for mapping a quantum circuit to a quantum processor. A light cone analysis is performed on the quantum circuit. A light cone refers to a map of the effects that the circuit operations have on the final observable value. Circuit operations that fall outside or within one or more light cones of non-identity operators in an observable based on the light cone analysis on the quantum circuit are then determined. The greater the number of overlapping or individual light cones that such circuit operations lie within, the greater the impact that such circuit operations have on the final observable value. A circuit mapping of the quantum circuit on the quantum processor is then determined based on the determination of which circuit operations fall outside or within the one or more light cones of non-identity operators in the observable.

A planar filament for an x-ray tube can have a different cross-sectional area at different locations. In regions of smaller cross-sectional area, there can be higher current density, and thus increased heating and higher temperature of the wire. In regions of larger cross-sectional area, there can be lower current density, and thus decreased heating of the wire. Regions of larger cross-sectional area can also be stronger, thus reducing early filament failures. Wider regions can have increased area for electron emission. By adjusting the cross-sectional area and width of the wire at different locations, electron emission can be largely confined to a center of the filament, and filament life can increase.

A quantum computer system comprises first and second registers which are used to separate a quantum state into multiple subspaces of a 2n dimensional Hilbert space. A quantum state comprising 2n elements is defined on the first register, the first register comprising n qubits; a quantum state is defined on the second register, the second register comprising one or more qubits; and receiving a value k, where k is a binary integer such that 0 =< k =< n. The method further performing a bit-wise iteration process comprising: (i) performing a quantum entanglement between the registers to separate the quantum state on the first register into distinct subspaces of the Hilbert space which are indexed by the entangled values on the second register, and (ii) measuring an outcome on the second register to find a match with a portion of k, wherein said portion of k increases incrementally with the iteration process until the match is with all of k. The bit-wise iteration is used to separate the quantum state on the first register into subspaces of the Hilbert space, wherein elements of the subspaces have different Hamming weights, and one subspace contains only elements of Hamming weight k.

The invention discloses a method for detecting a low-frequency electromagnetic field based on Rydberg atoms. According to the method, on the basis that Rydberg atoms have a unique response mechanism for an external electric field and a magnetic field, the Rydberg atoms can convert modulation of a low-frequency electromagnetic field into relevant physical quantity changes of a detection light field under an appropriate quantum regulation and control means, and therefore precise measurement of the low-frequency electromagnetic field is achieved; according to the method, a stable local bias field is applied to the atomic gas chamber, so that the measurement process occurs in a linear conversion area, and the measurement accuracy and sensitivity are remarkably improved; furthermore, the gas chamber condition, the laser driving system, the detection light path and the specific frequency component extraction process are optimized, so that the signal-to-noise ratio of low-frequency electromagnetic field signal measurement can be remarkably improved, and the detection capability of the system is enhanced. According to the method and device, the design thought is clear, the structural complexity is low, good environmental adaptability is shown, and an efficient and reliable means is provided for low-frequency electromagnetic field measurement.

The invention provides an adaptive weight multi-particle beam flow transmission simulation method and device, and the method belongs to the technical field of particle accelerators, and specifically comprises the steps: dividing a to-be-processed macro particle beam to form a plurality of groups of macro particles; configuring a relative weight for each group of macro particles according to the density distribution characteristics of the macro particle beams; sampling each group of macro particles in combination with the relative weight of each group of macro particles to obtain a corresponding sampling result; determining the weight of each macro particle in each sampling result in combination with the relative weight of each macro particle in each sampling result; determining similarities of a candidate beam bunch and a macro particle beam bunch in different dimensions, wherein the candidate beam bunch is formed by collecting sampling results configured with weights of macro particles; under the condition that the similarity meets a beam dynamics simulation condition, determining the candidate beam bunch as a new macro particle beam bunch; the new macro particle beam is used for replacing the macro particle beam to carry out multi-particle beam flow dynamic simulation, and the evolution process of beam transmission in the accelerator is described.