75 results about "Double quantum" patented technology

In a semiconductor laser having an active layer of double-quantum-well structure that includes two InGaN well layers each of which has a thickness of 5 nm, a threshold current deteriorates to a relatively small degree while differential efficiency is improved considerably in a region having a light confinement coefficient Γ of 3.0% or less. On the other hand, with the light confinement coefficient Γ becoming less than 1.5%, the threshold current increases considerably while the amount of improvement in differential efficiency becomes small. It is therefore preferable that the lowest limit to the light confinement coefficient Γ be about 1.5%. The differential efficiency of 1.6 W/A or more is obtained with the light confinement coefficient Γ being 3.0% or less, and the differential efficiency of 1.7 W/A or more is obtained with the light confinement coefficient Γ being 2.6% or less.

The invention relates to a design and realization method of an array multiplier based on the reversible 'ZS' series of gates. The method establishes a one-to-one relationship between the reversible definitions in a quantum computer and the inputs or outputs in a truth table and designs a series of reversible logic gates-'ZS1', 'ZS2' and 'ZS3' gates, which have the one-to-one relationship with theinputs or outputs in the truth table, and a quantum circuit diagram of the series of gates only containing double-quantum bit controlled gate and single bit gate. The method is based on Toffoli gate and designs three adding circuits which receive different symbol inputs and obtain the corresponding symbol outputs; the method is based on the 'ZS' series of gates and designs a multiplication circuit structure with the best reversible optimization, namely a quantum array multiplier. The reversible array multiplier can adopt a method similar to the manual calculation to complete the multiply operation with symbolic number in a higher computing speed; and the regularity of the internal structure is high and the internal structure is easy to extend. The design and realization method of the invention is applicable to the circuit design and application of the quantum system and realizes a certain promotion to the design and realization of the quantum large scale integrated circuits.

One embodiment described herein provides a system and method for simulating behavior of a quantum circuit that includes a plurality of quantum gates. During operation, the system receives information that represents the quantum circuit and constructs an undirected graph corresponding to the quantum circuit. A respective vertex within the undirected graph corresponds to a distinct variable in a Feynman path integral used for computing amplitude of the quantum circuit, and a respective edge corresponds to one or more quantum gates. The system identifies a vertex within the undirected graph that is coupled to at least two two-qubit quantum gates; simplifies the undirected graph by removing the identified vertex, thereby effectively removing the two-qubit quantum gates coupled to the identified vertex; and evaluates the simplified undirected graph, thereby facilitating simulation of the behavior of the quantum circuit.

The invention discloses a polarized SAR image object classifying method based on multi-quantum ridgelet representation. The polarized SAR image object classifying method based on multi-quantum ridgelet representation solves the problem of insufficient feature representation, low classification precision and high time complexity of the prior art. The method is implemented through the steps of, firstly, extracting the image features of a polarized SAR image; secondly, combining the features into a feature matrix and performing normalization; thirdly, selecting a training data set and a testing data set from the feature matrix; fourthly, training the training data set through a double-quantum ridgelet network; fifthly, training and classifying the training data set through an artificial neural network (NN) classifier; sixthly, classifying the test data set through a trained classifier. By means of the multi-quantum ridgelet neural network, the polarized SAR image object classifying method based on multi-quantum ridgelet representation is flexible in structure and improves the presentation ability of the image features of the polarized SAR image, thereby effectively improving the classification precision of the SAR image, reducing time complexity and being applicable to classification of complex images.

Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit.

The invention discloses a superconducting quantum bit structure with adjustable adjacent bit coupling strength. The superconducting quantum bit line comprises a first superconducting quantum bit line,including a capacitor C1, an inductance (shown in the specification) and a Josephson junction (shown in the specification). The capacitor C1 is connected with the inductor C1 in series, and the capacitor C1 is connected with the inductor C1 in series. The capacitor C1 is connected with the inductor C1 in series. The inductor C1 is connected with the inductor C1 in series. The capacitor C1 and theinductor (1) are connected in series, and the capacitor C1 and the inductor (1) are connected in parallel after the capacitor C1 and the inductor (1) are connected in series. The capacitor C1 and theinductor (1) are connected in series. Two ends of each of the first end and the second end of each of the first end, the second end and the third end. The superconducting quantum bit line also comprises a second superconducting quantum bit line, including a capacitor C2, an inductance (shown in the specification) and a Josephson junction (shown in the specification). The capacitor C2 and the inductor C2 are connected in series, and the inductor C2, the capacitor C2 and the inductor C2 are connected in series. The capacitor C2, the inductor C2 and the inductor C2 are connected in series. Capacitor C2 and inductor (shown in the specification) which are connected in series are connected to the capacitor C2 and the inductor (shown in the specification) in parallel, and the capacitor C2 and the inductor (shown in the specification) are connected to the capacitor C2 and the inductor (shown in the specification) in series. The number of the terminals is two, and the number of the terminals is two. The superconducting quantum bit structure also comprises a coupling loop, including a Josephson junction Lk forming a loop, an inductance (shown in the description) and an inductance (shown inthe description) as well as inductance (shown in the description) wherein the formula (1) is shown in the specification, and the formula (2) is shown in the specification. One end of the Josephson junction Lk is connected between the capacitor C1 and the inductor (please see the formula in the specification), and the other end of the Josephson junction Lk is connected between the capacitor C1 andthe inductor (please see the formula in the specification). The other end of the capacitor C2 is connected between the capacitor C2 and the inductor (please see the formula in the specification). Theother end of the capacitor C2 is connected between the capacitor C2 and the inductor (please see the formula in the specification); Inductance (shown in the description) and inductance (shown in the description) as well as inductance (shown in the description) According to the structure, the fidelity of the double-quantum-bit CZ gate is further improved, so that the precision of quantum calculation is improved, the expansibility is high, and the application of superconducting quantum calculation is promoted.

The invention discloses a double-quantum-dot nano complex nitrogen monoxide ratiometric fluorescent probe and a preparation method thereof, belonging to the fields of nano technology and chemical analysis. The preparation method of the probe comprises the following steps: (1) carrying out reaction on mercaptopropionic-acid-stable CdSe quantum dots and a silane agent to obtain an amino-surface-functionalized CdSe@SiO2 core-shell complex; (2) dropwisely adding the mercaptopropionic-acid-stable CdSe quantum dot dispersion solution into the core-shell complex system to prepare a CdSe@SiO2-CdTe nano complex; and (3) introducing NO into the nano complex system, determining the fluorescence emission spectrum of the system, fitting the linear relationship between the CdTe/CdSe quantum dot ratiometric fluorescence intensity and NO concentration, and establishing the NO ratiometric fluorescent probe based on the CdSe@SiO2-CdTe nano complex. Compared with the prior art, the ratiometric fluorescence intensity introduced into the fluorescent probe can obviously enhance the NO detection accuracy and feasibility, and has important application value.

The invention discloses a niobium pentoxide/carbon double-quantum-dot nanometer composite material, a method for preparing the same and application of the niobium pentoxide/carbon double-quantum-dot nanometer composite material. The niobium pentoxide/carbon double-quantum-dot nanometer composite material comprises niobium pentoxide and carbon double quantum dot. The niobium pentoxide quantum dot and the carbon double quantum dot are closely bonded with each other; the mass fraction of the carbon quantum dot in the niobium pentoxide/carbon double-quantum-dot nanometer composite material is 20-40%. The niobium pentoxide/carbon double-quantum-dot nanometer composite material, the method and the application have the advantages that gaps are reserved between particles of the niobium pentoxide/carbon double quantum dots, and accordingly the niobium pentoxide/carbon double-quantum-dot nanometer composite material has large specific surface areas; the niobium pentoxide/carbon double-quantum-dot nanometer composite material with the structure is favorable for sufficient contact of electrolyte solution and active substances and further can effectively adapt to volume expansion of materials in charge and discharge procedures, and accordingly the electrochemical performance of the niobium pentoxide/carbon double-quantum-dot nanometer composite material can be greatly improved when the niobium pentoxide/carbon double-quantum-dot nanometer composite material is used as a negative electrode material for lithium ion batteries; precursors of niobium and carbon quantum dots are synthesized by the aid of hydrothermal processes at first and then are calcined in argon atmosphere to obtain the niobium pentoxide/carbon double-quantum-dot nanometer composite material; the method is convenientand easy to operate, reaction conditions can be controlled, and scale-up experiments can be facilitated.

A method for obtaining NMR (=nuclear magnetic resonance) spectra of quadrupolar nuclei having spin l>½ using magic angle spinning (=MAS) in solid powders and transfer of coherences from a neighboring nucleus with spin S= 1/2 to single- or double-quantum transitions of quadrupolar nuclei having spin l>½, is characterized in that the transfer of coherences occurs through a combination of scalar and residual dipolar splittings. With the inventive method improved NMR-spectra can be obtained from which parameters can be extracted, which can be related to the structure and internal dynamics of solids containing the quadrupolar nuclei.

A photoelectric conversion method used for a nano junction type photovoltaic device includes the steps that a semiconductor heterojunction is prepared, a first metal electrode, a second metal electrode and a third metal electrode are manufactured on the surface of the semiconductor heterojunction and sequentially arranged in parallel, and each metal electrode comprises two electrode parts which are spaced and arranged oppositely; the metal electrodes are powered on so as to form a double-quantum-dot system; a first semiconductor quantum dot is formed between the first metal electrode and the second metal electrode, and a second semiconductor quantum dot is formed between the second metal electrode and the third metal electrode; the bias voltage on the first metal electrode, the second metal electrode and the third metal electrode is adjusted, so that only two single electron states of the double-quantum-dot system work when the double-quantum-dot system conducts electricity, wherein the double-quantum-dot system comprises the first semiconductor quantum dot and the second semiconductor quantum dot, only one excitation electron exists in the double-quantum-dot system at most when the double-quantum-dot system conducts the electricity, and the excitation electron absorbs photons with preset energy under the action of tunneling between dots.

In one aspect, there is provided a method for transmitting a two-qubit state. The method includes: propagating the two-qubit state onto a transmission waveguide, wherein the propagating includes distributing the two-qubit state about a certain phase; and transmitting the two-qubit state through the transmission waveguide using a pump pulse having the certain phase, wherein the pump pulse is provided in a manner so that the transmission waveguide functions as an optical phase sensitive amplifier (OPSA).

The invention belongs to the field of quantum computing, and particularly discloses a double-quantum logic gate implementation method based on MPI multi-process, which comprises the following steps of: calling 2M processes based on MPI communication; wherein M is an integer, M is greater than or equal to 1, and each process number is from 0 to 2M-1; configuring n quantum bits, initializing 2N quantum states of the N quantum bits, distributing each quantum state to each process, wherein N is an integer, and N is greater than or equal to M + 2; determining a to-be-calculated quantum state according to the control bit n1 and the operation bit n2 of the double-quantum logic gate, the to-be-calculated quantum state appearing in groups, and each group comprising four quantum states; wherein n1 and n2 are integers, and n1 is not equal to n2; determining a target process for storing each group of to-be-calculated quantum states; and running the target process to obtain the quantum state amplitude of the quantum bits after the double quantum logic gates act. According to the invention, the calculation capability and calculation efficiency of quantum calculation based on multiple quantum bits and double quantum logic gates can be improved.

Disclosed herein is a structure and method for manipulating a spin state, regarded as important in the field of spintronics, by which the distribution of spin-up and spin-down states of carriers in a hybrid double quantum disk structure, composed of a diluted magnetic semiconductor and a ferroelectric compound semiconductor, is manipulated through dipole polarization switching of the ferroelectric compound semiconductor without a change in bias. Giant Zeeman splitting properties of the diluted magnetic semiconductor and polarization properties of the ferroelectric compound semiconductor are applied in conjunction with the Pauli exclusion principle, thus enabling the combination or separation of carriers in spin-up and spin-down states in the hybrid double quantum disk structure. The spin relaxation time in the structure is on the order of microseconds, during which the spin state is well-defined, and therefore, the structure can be applied to microprocessors having gigahertz clock speeds.

The invention discloses a GaN-based laser diode epitaxial structure and a preparation method thereof. The GaN-based laser diode epitaxial structure is sequentially provided with a GaN single crystal substrate, an n-type GaN layer, an n-type limiting layer, a lower waveguide layer, an active region, an upper waveguide layer, a p-type limiting layer and a p-type GaN layer from bottom to top in a stacked mode, wherein the lower waveguide layer is an n<->-Aly2Ga<1-y2>N+n<->-GaN+n<->Inx1Ga<1-x1>N/GaN superlattice composite waveguide layer; the active region is of an asymmetrically doped InGaN/GaN double quantum well structure, and the upper waveguide layer is of a u<->Inx4Ga<1-x4>N/GaN superlattice and u<->GaN+p<->Aly4Ga<1-y4>N composite structure. The brand-new GaN-based laser diode epitaxialstructure is obtained by optimally designing a GaN-based laser high-quantum-efficiency gradient In component trapezoidal active region structure and further designing a novel optical waveguide layer structure. The GaN-based laser diode epitaxial structure is used as a laser, and when optical pump lasing is carried out, the half-peak width is narrow, and the light beam quality is high.

The invention discloses a quantum bit long-range coupling device based on phonon assistance. The invention aims to realize long-range coupling of multiple quantum bits on a chip by using a mechanical mode in a single carbon nanotube structure. Through voltage regulation, a double-quantum-dot structure can be formed in the carbon nanotube, and quantum bits can be constructed. The mechanical mode of the carbon nano tube can be used as a phonon cavity to provide phonons, and the phonons can realize coherent long-range transmission along the carbon nano tube. The long-range coupling of the double quantum dots is realized by virtue of the interaction between the double quantum dots and phonons and the interaction between the phonons. The device provided by the invention is simple in structure and small in size, and a new technical route is provided for extensible quantum calculation.

Provided is a recording apparatus including a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected, an optical separation unit, an objective lens, a light reception element, a pulse detection unit, a reference signal generation unit, a phase comparison unit, a recording signal generation unit, and a control unit.

The disclosure describes various techniques to control of small angle Mølmer-Sorensen (MS) gates and to handle asymmetric errors. A technique is described that implements a two-qubit calibration circuit with two MS gates, where a parameter θ represents an amount of entanglement of the MS gate. The calibration circuit is run for several values of θ to measure observed parity signals that are direct measurements of the values of θ. Calibration information is generated that describes the relationship between θ and the parity signals, and such calibration information is then provided to arbitrarily calibrate one or more MS gates in a quantum simulation. Another technique is described for using the calibration information in quantum simulations, including for quantum chemistry simulations. Yet another technique is described for handling system-based asymmetric errors in the measurements of different qubit states in different types of quantum circuits, including, for example, the calibration circuit mentioned above.

The invention discloses a preparation method of a double-quantum dot modified flower-like three-dimensional graphene and a photocatalytic material. Specifically, the method includes: preparing three-dimensional graphene on foam nickel; preparing an electrodeposition precursor solution containing Au; and preparing an Au@TiO2@3DGFs composite material by electrochemical deposition: putting a three-dimensional graphene into the precursor solution to serve as a working electrode for deposition of TiO2 and noble metal Au double quantum dots, thus forming flower-like three-dimensional graphene with Au and TiO2 double quantum dots evenly distributed on the surface in the electrochemical deposition process. The three-dimensional graphene electron-hole pair prepared by the method provided by the invention has the characteristics of low recombination rate, high photoelectrocatalytic activity, and high sunlight utilization.

The invention provides a cross-linking density measurement method, which comprises the steps of acquiring a nuclear magnetic resonance double-quantum sequence and a plurality of preset regularization parameters, and determining a double-quantum growth signal and a reference attenuation signal of a to-be-measured sample by using the nuclear magnetic resonance double-quantum sequence; fitting the difference signal of the double-quantum growth signal and the reference attenuation signal, and determining the non-coupling component of the double-quantum growth signal; normalizing the double-quantum growth signal based on the uncoupled component and the reference attenuation signal, and calculating a normalized double-quantum growth signal; performing regularization inversion on the normalized double-quantum growth signal according to each preset regularization parameter, and determining a residual dipole coupling distribution result of the to-be-tested sample; and converting a residual dipole coupling distribution result into a cross-linking density distribution result by using a corresponding relationship between residual dipole coupling and cross-linking density. According to the invention, complete measurement of rubber cross-linking density distribution is realized, and the reliability of a final result is ensured.