13 results about "Ground state" patented technology

The application discloses a kind of based on ensemble rare earth ions double quantum bit controlled gate construction method, it is related to quantum control technical field, it includes to double quantum bit frequency site selection, and respectively as control bit, target bit;Utilize the blocking effect generated by the dipole-dipole interaction between double quantum bits to construct controlled gate, including: to control bit apply light pulse driving control bit is from ground state transition to excited state;To target bit apply single quantum gate to drive its evolution, and apply compensation pulse;To control bit apply light pulse driving control bit from excited state de-excitation to ground state.The application utilizes the interaction of the light pulse and quantum system medium that can be optimized to produce arbitrary geometric quantum logic gate on target quantum bit, and simultaneously by using the blocking effect caused by dipole-dipole interaction, the evolution of target bit quantum bit can be constrained by control bit.

A method (100) for determining a ground state (1000) of a quantum system is disclosed, comprising the following steps: 6) determining (102) the thermal state (1020) of the quantum system at a temperature value (1001', 1001) by optimizing the free energy (3020) of the thermal state (1020) at the temperature value (1001', 1001) by iteratively adjusting gate parameters (1022', 1022) by means of a variational quantum thermalizer (1010) until a first termination criterion is met; 7) checking (1025) whether the previously found thermal state meets a second termination criterion; 8) if the second termination criterion is not met (10250): decreasing (1026) the temperature value (1001', 1001); initializing (301) the quantum circuit (1011) of the variational quantum thermalizer using the gate parameters (1022', 1022) from the last iteration of step 2); repeating steps 2) and 3); 9) if the second termination criterion is met (10251): providing (103) an energy spectrum (1030) of the quantum system using the gate parameters (1022) of the last iteration of step 2) before the second termination criterion (10251) is met; determining (104) the ground state (1000) of the quantum system by selecting the state of the energy spectrum that is assigned the lowest energy.

A method for measuring a preferably static magnetic field is claimed, comprising the following steps in this order: i) Excitation of a valence electron of one or more alkali atoms (2) from a ground state to an initiation state in a manifold with principal quantum number n; ii) Application of a ½ control pulse to generate a superposition, preferably a uniformly distributed superposition, between the initiation state and a control state; iii) Application of a sequence of circulation pulses and one or more control pulses, preferably with specific time intervals, to shift the valence electron within the manifold of the initiation state; iv) Application of a further ½ control pulse for coherent mixing of the populations in the initiation state and control state; v) Measurement of the state of the valence electron, and preferably calculation of the magnetic field;

This invention discloses a molecular dynamics calculation method and system based on quantum simulation. The method first applies a discrete quantum Fourier transform to the atomic coordinates of the molecular system, mapping the original plane wave basis to a system containing only O(N) atoms. 2 The invention constructs a plane-wave bibasic quantum mechanics equation; then, it constructs and solves the electronic structure Hamiltonian on a quantum computer to obtain the ground state energy. This quantum energy is combined with the classical empirical potential energy according to predetermined weighting coefficients to calculate the total synthesized energy, from which the atomic forces are determined. The integration time step is then adaptively adjusted based on a comparison of the quantum energy change between consecutive time steps with a preset threshold. This adaptive mechanism shortens the time step to ensure accuracy when quantum effects are significant, and lengthens the step to improve efficiency when changes are gradual. This invention significantly reduces Hamiltonian complexity, balancing quantum accuracy and classical efficiency, and is applicable to various fields such as drug screening, materials design, and catalytic reaction simulation.

Selective frequency dissipation is implemented that enables cooling of energy gap protected qubits such that excited energy states resulting from heating or other undesired processes are returned to a lower excited energy state or a ground state manifold, thus reducing the probability of errors. Also, the selective frequency dissipation inhibits leakage from the energy gap protected qubits when in the ground state. Additionally or alternatively, Hamiltonian engineering by inducing parity rotations is implemented to decouple the wells of the energy gap protected qubit to further reduce errors when leakage does happen.

The application relates to the technical field of strong-field high-harmonic generation, and particularly discloses a double-electron quantum correlation quantitative method and system based on Bohm mechanics, which comprises the following steps: establishing a time-dependent Schrodinger equation containing an external laser field, obtaining a system ground state wave function and generating N pairs of Bohm particles initial coordinates, and performing time evolution on the wave function; according to the evolved wave function, the accurate velocity field and the accurate motion trajectory of each Bohm particle are calculated; based on the marginal probability density and the marginal probability flow density, the marginal velocity field not containing instantaneous quantum correlation effects is constructed, and the corresponding correlation-free reference trajectory is generated; the accurate trajectory is compared with the reference trajectory, and the correlation model of the correlation quantum potential and the high-harmonic radiation intensity is established. Through comparison of the accurate Bohm trajectory and the correlation-free reference trajectory constructed based on the marginal velocity field, the quantum correlation effects in a strong-field double-electron system are quantitatively separated and visually output.

This invention discloses a debugging method and apparatus for an atomic gravimeter, and the atomic gravimeter itself, relating to the field of atomic gravimeter technology. This invention can control the Raman light source to change the frequency difference between two Raman beams, causing the two beams to interact with atomic groups in a vacuum chamber. A fluorescence collection device can detect the ground state energy level population of atoms in the vacuum chamber. The main unit can plot a Raman spectrum showing the probability of an atom being in the target ground state as a function of the frequency difference, based on the ground state energy level population. By determining whether the Raman spectrum meets the preset conditions corresponding to the target polarization state, the polarization state of the Raman light in the atomic gravimeter can be judged to be in the desired state.

A non-transitory computer-readable storage medium storing a solution search program that causes at least one computer to execute a process, the process includes reducing, when searching for a ground state of the Ising model that represents a problem by obtaining a state change of the Ising model, a strength of a magnetic field applied to the Ising model according to a first annealing schedule from an initial state of the Ising model; and reducing, after a quantum phase transition occurs in the Ising model, the strength of the magnetic field according to a second annealing schedule.

The application discloses a multi-physical field coupling and impedance spectrum analysis flame detector nondestructive testing method and system, and relates to the technical field of helicopter flame detector nondestructive testing.The temperature field and the electromagnetic field are coupled to replace light, so that a simulation environment of fire radiation effect is provided for the flame detector, and the photochemical reaction of the photoelectric material caused by light is avoided; the error is eliminated through wide frequency scanning and the four-electrode method, the impedance spectrum is obtained through inversion calculation, and the physical parameters are obtained through deconstruction, so that the problem that the continuous relaxation process information contained in the wide frequency data is lost in traditional impedance analysis is avoided; the classical physical parameters of the sensor fault are mapped into the Hamiltonian of the quantum system, the fault is sensed by solving the ground state, and the defects that the classical machine learning is easy to fall into local optimization when processing high-dimensional, nonlinear and strongly correlated fault features, and the model is poor in interpretability.

The present application relates to an apparatus and a method for optimization. An optimization apparatus solves the ground state of an Ising model by running a simulation of state changes of the Ising model that occur when a magnetic field applied to the Ising model representing a target problem is decreased. In doing so, the optimization apparatus adds values corresponding to noise to some coefficients used in the simulation. Then, the optimization apparatus performs a first process of real-time propagation that decreases the strength of the magnetic field with the time progression in the simulation and a second process that decreases the energy of the Ising model based on an imaginary-time propagation method.

The application provides a kind of quantum bit fast reading method based on resonant cavity field strength strict control, belong to quantum computing and quantum information processing technical field, this method includes: extracting the readout resonant cavity coupled with quantum bit, obtains the key parameter of readout resonant cavity;Set driving signal frequency and calculate the detuning of ground state and excited state;Design pulse-maintain two-section type driving signal, determine the matching relationship of two pulse amplitudes, generate two-section type microwave driving signal;Two-section type microwave driving signal is applied to readout resonant cavity, carry out the fast response of resonant cavity field strength;Establish strict stable condition, so that cavity field reaches stable value strictly;Based on the coupling effect of superconducting quantum bit and readout resonant cavity, determine quantum bit state through dispersion model;After reading, quickly empty the photon in cavity to vacuum state, realize fast reset.The application realizes resonant cavity field strength fast response and reset through field strength strict control, realizes the fast, accurate reading of quantum bit.

The invention relates to a method for determining an error-corrected expectation value of an observable of a quantum system using a classical computer, comprising the following steps: • Providing a first expected value of an observable, which depends on a first distance measure, where the first distance measure specifies a spatial separation between a first qubit group and a second qubit group; • Providing at least one second expected value of the observable, which depends on a second distance measure; • Determining a customized fit function using the following steps: ◯ Provide a fit function that includes at least one fit parameter and depends on the distance measure; ◯ Adjusting the fit parameters of the fit function to the first expected value and the second expected value; • Determining an error-corrected expected value of the observable by evaluating the fitted function for the case where the distance measure takes on a value greater than the first distance measure and the second distance measure; • Providing the error-corrected expected value.