31 results about "Double quantum" 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.

This invention discloses a method and device structure for improving the electrical transport properties of etched graphene quantum dots, belonging to the field of low-temperature transport testing technology. The method includes the following steps: fabricating etched graphene quantum dot devices; performing preliminary electrical transport characterization by cooling; and undergoing several cycles of "sample electrode grounding protection – heating to above 200K or room temperature – cooling again – electrical transport characterization" to improve the electrical transport properties of the device, enabling subsequent observation and manipulation of the quantum dot's fine charge stability map. The optimized method of this invention, through several heating and cooling thermal cycles, successfully adjusts the coulomb blocking region of the graphene quantum dots from hundreds of volts towards zero, facilitating the application of a gate voltage. Furthermore, the charge stability map of the two quantum dots is significantly optimized and improved, greatly increasing the yield of etched graphene quantum dot devices. In addition, the optimized method of this invention is simple to operate and has significant effects, making it suitable for widespread application.

The present disclosure relates to an apparatus and method for quantum computing using a plurality of neutral atoms in an optical trap array wherein a first internal state of the neutral atoms is used as a qubit ground state 0gt; the second internal state is used as a quantum bit excitation state 1gt; . According to the present disclosure, a local single qubit gate operation can be performed on a qubit, comprising locally and selectively irradiating with a qubit addressing laser at a first qubit addressing laser frequency, which is prepared as a qubit ground state 0gt; and a quantum bit excited state 1gt; a superposition state sgt; the quantum bit is used for causing a quantum bit ground state 0gt; and a quantum bit excited state 1gt; and the differential stark displacement is realized. Furthermore, a local dual qubit gate operation may be performed on the pair of qubits, including locally and selectively irradiating with a qubit addressing laser at a second qubit addressing laser frequency prepared as a qubit ground state 0gt; a pair of qubits for a third internal state cgt, preferably via neutral atoms; coupling the quantum bit pair to a Rydberg state rgt of a neutral atom; a third internal state cgt; the method can be used as a quantum bit ground state 0gt; a Rydberg state rgt is obtained; and the intermediate state of two-photon transition is realized.

Techniques are provided for mediating interactions (e.g., long range interactions) between quantum bits to facilitate quantum computing operations such as two-qubit gate operations. A device comprises a first quantum bit, a second quantum bit, and a coupling bus connecting the first quantum bit and the second quantum bit. The coupling bus comprises a plurality of transmission line resonators which are coupled in series, and at least one tunable inductive coupler to control a coupling between a first transmission line resonator and a second transmission line resonator of the plurality of transmission line resonators.

The embodiment of the invention provides a frequency determination method and device, electronic equipment and a storage medium. According to the scheme, the method comprises the following steps: obtaining a first corresponding relation between coupler frequencies and leakage rates according to operation of at least one resonance type double-quantum logic gate on a first quantum bit and a second quantum bit in a target system under different coupler frequencies; based on the first corresponding relation, the coupler frequency corresponding to the lowest leakage rate is selected as the target frequency, and the target frequency is the frequency of a control signal applied to the adjustable coupler when the first quantum bit and the second quantum bit execute the resonance type double-quantum logic gate operation. Through the technical scheme provided by the embodiment of the invention, the frequency of the control signal applied to the adjustable coupler during the execution period of the resonance type double-quantum logic gate can be determined, so that an observer error is effectively inhibited, and the fidelity of quantum calculation is improved.

This invention discloses a highly self-assembled dual quantum dot / graphene heterojunction broadband memristor, its fabrication method, and its applications, belonging to the field of inorganic semiconductor technology. The method includes the following steps: mixing highly self-assembled cerium oxide quantum dot ink and PbS quantum dot ink with a graphene dispersion and stirring until homogeneous to form a uniformly loaded quantum dot / graphene dispersion; then using the quantum dot / graphene dispersion to construct a dual quantum dot / graphene heterojunction film on a silicon wafer surface, thus obtaining the dual quantum dot / graphene heterojunction broadband memristor. This invention overcomes the inherent limitations of the photoresponse range of single materials, achieving broadband optoelectronic memristor behavior in the ultraviolet to near-infrared bands. Simultaneously, the memristor of this invention exhibits rich synaptic plasticity under light pulse modulation, providing core support for constructing a novel integrated optoelectronic system for broadband sensing, storage, and processing. It possesses strong technical adaptability and industrialization prospects in cutting-edge fields such as bionic vision, optical neural networks, and intelligent sensing.

Embodiments of the present application provide a double quantum dot model simulation method and device, electronic equipment and storage medium. The scheme is as follows: a double quantum dot model is constructed as a to-be-simulated model; a Hamiltonian including a first energy is generated according to a performance parameter of the to-be-simulated model, wherein the first energy is a tunneling energy between electrons in the to-be-simulated model due to the spin-orbit coupling effect when the left and right quantum dots have opposite spins; based on the Hamiltonian, a target tunneling coefficient between source-drain electrodes and the left and right quantum dots in the to-be-simulated model is calculated; a target function relationship indicating a current in the to-be-simulated model is determined according to the target tunneling coefficient and a preset master equation, and the preset master equation is used to describe the dynamic change of the electron or hole distribution corresponding to the tunneling process in the to-be-simulated model; and the to-be-simulated model is simulated for drain current according to the target function relationship. Through the technical scheme provided by the embodiments of the present application, the drain current simulation of the double quantum dot model can be realized.

Aspects of the present disclosure relate to systems and methods in quantum information processing (QIP). The method includes determining a temporal profile of a trapping potential of an ion trap configured to trap a first trapped ion and a second trapped ion of an array of trapped ions for QIP and obtaining at least one characteristic of a first optical beam that is applied to the first trapped ion. The method includes synchronizing the at least one characteristic of the first optical beam and the temporal profile of the trapping potential and simultaneously applying the first optical beam to the first trapped ion based on the at least one characteristic and the trapping potential having the temporal profile to the ion trap. Optical beams including the first optical beam are applied to the first trapped ion and the second trapped ion.

The present disclosure provides a mounting method in which is used a linear optical circuit for quantum measurement that is a so-called pairwise fusion gate (PFG) having a function for stochastically projecting two inputted qudits onto the quantum entangled state of a two-qubit subspace. Specifically, provided is a pairwise fusion gate characterized by comprising a linear optical element and a photon detector, the pairwise fusion gate furthermore being characterized in that: the linear optical element and the photon detector are configured so that an input which has two d-dimensional qudits defined using d-rail coding (where d is an integer equal to or greater than 3), and in which there is no quantum entanglement between the two qudits, is stochastically projected onto a quantum entanglement state in a two-qubit subspace; and measurement results from the photon detector are used in determining the specific two-qubit subspace in which the projection onto the quantum entanglement state has been made.

Aspects of the present disclosure relate generally to systems and methods for use in the implementation and / or operation of quantum information processing (QIP) systems, and more particularly, to a fast single-mode spectroscopy technique that may be used in trapped-ion QIP systems. A method is described that includes performing a first measurement scan (full scan) across all motional modes of an ion chain in a trap followed by a second measurement scan on a single motional mode of the motional modes (single-mode scan). The second measurement scan determines a frequency shift associated with the single motional mode, which is applied to adjust the frequencies of all the motional modes. An implementation of two-qubit gates for quantum computations is based on the adjusted frequencies. A quantum computer or QIP system is also described that is configured to implement and perform the method described above.

A method for qubit initialization, comprising the steps of: (i) setting a dual qubit state of a pair of spin qubits to an arbitrary state; (ii) verifying a qubit state associated with the pair of spin qubits for a corresponding target state; and (iii) in response to determining that the qubit state is not the target state at step (ii), repeating steps (i) to (ii) until the qubit state is determined to be the target state. Determining the qubit state as the target state includes performing one or more Follicle spin blocking (PSB) checks and at least one dual qubit state transition operation on the pair of spin qubits.

The invention discloses a double-quantum-bit controlled gate construction method based on ensemble rare earth ions, and relates to the technical field of quantum control, and the method comprises the steps: carrying out the site selection of double-quantum-bit frequency, and taking the double-quantum-bit frequency as a control bit and a target bit; a controlled gate is constructed by using a blocking effect generated by dipole-dipole interaction between double quantum bits. The method comprises the following steps: applying an optical pulse to a control bit to drive the control bit to transition from a ground state to an excited state; applying a single quantum gate to the target bit to drive the target bit to evolve, and applying a compensation pulse; and applying an optical pulse to the control bit to drive the control bit to be de-excited from the excited state to the ground state. According to the invention, any geometric quantum logic gate is generated on a target quantum bit by utilizing the interaction of optimizable light pulses and a quantum system medium, and meanwhile, the evolution of the target bit quantum bit can be restrained by a control bit by utilizing a blocking effect caused by dipole-dipole interaction.

Techniques are provided for mediating interactions (e.g., long range interactions) between quantum bits to facilitate quantum computing operations such as two-qubit gate operations. A device comprises a first quantum bit, a second quantum bit, and a coupling bus connecting the first quantum bit and the second quantum bit. The coupling bus comprises a plurality of transmission line resonators which are coupled in series, and at least one tunable inductive coupler to control a coupling between a first transmission line resonator and a second transmission line resonator of the plurality of transmission line resonators.

Arrays of optically trapped neutral atoms are a promising architecture for the realization of quantum computers. In order to run increasingly complex algorithms, it is advantageous to demonstrate high-fidelity and flexible gates between long-lived and highly coherent qubit states. In this work, we demonstrate a universal high-fidelity gate-set with individually controlled and parallel application of single-qubit gates and two-qubit gates operating on the ground-state nuclear spin qubit in arrays of tweezer-trapped Ytterbium-171 atoms. We utilize the long lifetime, flexible control, and high physical fidelity of our system to characterize native gates using single and two-qubit Clifford and symmetric subspace randomized benchmarking circuits with more than 200 CZ gates applied to one or two pairs of atoms. We measure our two-qubit entangling gate fidelity to be 99.72(3)% (99.40(3)%) with (without) post-selection. In addition, we introduce a simple and optimized method for calibration of multi-parameter quantum gates. These results represent important milestones towards executing complex and general quantum computation with neutral atoms.

Techniques are provided for mediating interactions (e.g., long range interactions) between quantum bits to facilitate quantum computing operations such as two-qubit gate operations. A device comprises a first quantum bit, a second quantum bit, and a coupling bus connecting the first quantum bit and the second quantum bit. The coupling bus comprises a plurality of transmission line resonators which are coupled in series, and at least one tunable inductive coupler to control a coupling between a first transmission line resonator and a second transmission line resonator of the plurality of transmission line resonators.

A quantum device having an LC resonator circuit for performing a qubit measurement or readout is disclosed. The device comprises a silicon layer (601), a dielectric layer (603) disposed on the silicon layer (601) and forming a functional interface with the silicon layer (601), a first metal region (614) disposed on the dielectric layer 603, and a second metal region 624 disposed on the dielectric layer 603 and laterally separated from the first metal region (614). The first and second metal regions (614, 624) are arranged to be electrically connected such that a double quantum dot having a first state and a second state of a qubit can be induced to form at the functional interface under the first and second metal regions (614, 624). The double quantum dot provides a capacitor Cl in the LC resonator circuit, the capacitance of the double quantum dot depending on the state of the qubit. The first metal region (614) provides an inductor LI in the LC resonator circuit, the resonance frequency of the LC resonator circuit depending on the state of the qubit, such that the state of the qubit can be measured or inferred.

The application relates to the technical field of semiconductors, in particular to a double-layer quantum well structure for differential detection and a preparation method. The double-layer quantum well structure comprises, from top to bottom, a top contact layer, a first quantum well region, an intermediate contact layer, a second quantum well region and a bottom contact layer; and a top electrode, an intermediate electrode and a bottom electrode arranged on the top contact layer, the intermediate contact layer and the bottom contact layer respectively. Thus, a three-terminal device structure is formed, in which the two quantum well regions share the same intermediate electrode. Under the structure, when the two quantum well regions generate photoelectric current under light, the intermediate electrode can simultaneously obtain the current signals of the two quantum well regions, and by configuring the voltage applied on different electrodes, the intermediate electrode can output differential current, thereby providing a hardware basis for realizing differential detection.

This disclosure provides a quantum dot light conversion film, its preparation method, and a backlight module containing the same. The quantum dot light conversion film includes a base film, a first quantum dot film layer, a second quantum dot film layer, and an encapsulation film layer sequentially contacted together. The base film includes a barrier film layer and a PET film layer, and the barrier properties of the base film are WVTR ≤ 2 g / m². 2 The first quantum dot film layer comprises a first quantum dot and a first resin, the second quantum dot film layer comprises a second quantum dot and polyethylene terephthalate, and the encapsulation film layer comprises a second resin and inorganic oxide particles. The first and second quantum dots are selected from one or both of red and green quantum dots. The combined mass fraction of red and green quantum dots in the first quantum dot film layer is 0.01-1%. The dual quantum dot film layer structure can reduce the quantum dot content of the first quantum dot film layer, reduce the color dot fluctuation of this layer, and make it easier to produce products with stable color dot batches.

This disclosure relates to a rare metal-doped double quantum layer modified biosensor and its fabrication method, belonging to the field of photoanode thin film technology. The biosensor includes: a conductive substrate; and a photoanode thin film layer and an aptamer probe layer stacked on one side of the conductive substrate; the photoanode thin film layer includes a BiVO4 thin film layer, a Co-doped TiO2 quantum layer thin film layer, and a Rh-doped SrTiO3 quantum layer thin film layer sequentially disposed thereon. The method includes: 1. depositing a BiVO4 thin film layer on the conductive substrate; 2. alternately depositing TiO2 thin films and CoO2 thin films on the BiVO4 thin film layer. X 1. Form a Co-doped TiO2 quantum layer thin film; 2. Form a Rh-doped SrTiO3 quantum layer thin film; 3. Coat an aptamer probe solution to obtain a biosensor.

A method for performing quantum computing in a qubit processor is provided, the method comprising the steps of: configuring a first position (843) in a first position set (802) to perform (902) a first single-qubit operation; configuring a second position (844) in the first position set (802) to perform (902) a second single-qubit operation; configuring a first position (845) and a second position (846) in a second position set (803) to perform (906) a two-qubit interaction; and receiving at time t1, at the first position (843) in the first position set (802) (901) First qubit (831); at time t1, receive (901) second qubit (832) at the second position (844) in the first position set (802); wherein both the first and second qubits are provided in a first qubit group comprising n qubits, where n>2; perform (902) first single-qubit operation on the state of the first qubit (831) at the first position (843) in the first position set (802); perform (902) first single-qubit operation on the state of the second qubit (832) at the second position (844) in the first position set (802). (902) Second single-qubit operation; transferring (903) the first qubit (831) from the first position (843) in the first position set (802) to the first position (845) in the second position set (803); transferring (903) the second qubit (832) from the second position (844) in the first position set (802) to the second position (846) in the second position set (803); performing (906) two-qubit interaction between the first qubit (831) and the second qubit (832) in the second position set (803); transferring the first qubit (831) from the first position (843) in the first position set (802) to the second position (845) in the second position set (803); A qubit is transferred from a first position in a second set of positions to a first position in a readout set; a second qubit is transferred from a second position in a second set of positions to a second position in a readout set; at time t2, a first qubit of a second set of qubits is received at a first position in a first set of positions, where t2 > t1; at time t2, a second qubit of a second set of qubits is received at a second position in a first set of positions; the state of the first qubit at the first position in the readout set is read; and the state of the second qubit at the second position in the readout set is read.

The application discloses a kind of double quantum dot blending composite film environmental sensor and preparation method, a kind of double quantum dot blending composite film environmental sensor includes two groups of parallel interval arrangement substrate layer, two groups of the substrate layer between configuration has S type gas guide groove, the substrate layer is close to the side of S type gas guide groove interval and is equipped with several surface electrodes, the substrate layer between several surface electrodes is equipped with double quantum dot composite film, the beneficial effects of the present application are that the present environmental sensor uses amphoteric ion coordination group to improve the stability of inorganic perovskite quantum dot synthesis, to promote inorganic perovskite quantum dot and IV-VI group quantum dot blending structure growth, it is fast, high sensitivity, can simultaneously measure multiple gas and humidity parameters, response time is less than 20s, wide range of application, it can obtain required environmental sensor using one-step film preparation technology, preparation method is simple, fast and efficient, low in cost, suitable for large-scale production.

A method for quantum computing using neutral atoms in an array of optical traps, wherein a first internal state serves as qubit ground state |o>, and a second internal state serves as qubit excited state |1>, includes performing a local single-qubit gate operation comprising: locally and selectively illuminating a qubit prepared in a superposition state |s> of qubit ground state |0> and qubit excited state |1> with a qubit addressing laser at a first qubit addressing laser frequency to cause a differential Stark shift for the qubit ground state |0> and the qubit excited state |1>. The method also includes performing a local two-qubit gate operation comprising: locally and selectively illuminating a pair of qubits prepared in the qubit ground state |0> with the qubit addressing laser at a second qubit addressing laser frequency for coupling the pair of qubits to a Rydberg state |r>.

This invention discloses a method for improving the thermoelectric performance of an AB ring through lateral coupling and optical field irradiation. The method includes: first, coupling two quantum dots QD1 and QD2 into a dual-quantum-dot structure via a tunnel junction; spatially confining the dual-quantum-dot structure; coupling the dual quantum dots into the AB ring via the tunnel junction; placing left and right electrodes on opposite sides of the AB ring structure; applying thermal radiation to create a temperature gradient between the left and right electrodes; injecting electrons into the AB ring electrodes, causing electron transport under the influence of the lateral coupling of the dual quantum dots and the temperature gradient; and applying an adjustable optical field to the dual-quantum-dot structure. By optimizing the tunneling coupling strength between the quantum dots and adjusting the optical field frequency, the thermoelectric transport characteristics of the system are synergistically controlled, thereby obtaining enhanced spin thermoelectric potential and spin ZT coefficient. This invention optimizes thermoelectric performance by increasing the tunneling coupling strength between quantum dots and improving the optical field frequency, providing a foundation for designing fast-response, high-efficiency, and low-energy-consumption thermoelectric devices.

A quantum device is disclosed having an LC resonator circuit for performing qubit measurement or readout. The device comprises a silicon layer (601), a dielectric layer (603) disposed upon and forming a functional interface with the silicon layer (601), a first metallic region (614) disposed upon the dielectric layer 603, and a second metallic region (624) disposed upon the dielectric layer 603 and laterally separated from the first metallic region (614). The first and second metallic regions (614, 624) are arranged to be electrically connected such that a double quantum dot, forming a qubit having a first state and a second state, can be induced beneath the first and second metallic regions (614, 624) at the functional interface. The double quantum dot provides a capacitor C1 in the LC resonator circuit and the capacitance of the double quantum dot is dependent on the state of the qubit. The first metallic region (614) provides an inductor L1 in the LC resonator circuit, and the resonant frequency of the LC resonator circuit is dependent on the state of the qubit such that the state of the qubit can be measured or inferred.

The disclosed method of quench condensation of hydrogen isotopes for qubit applications includes using a non-hermetic sample cell geometry having an open sample cell with a chip holder surrounded by a radiation shield, and a completely opened geometry without extra chip shielding. The method may include growing thin epitaxial solid hydrogen films from the liquid phase and condensation of hydrogen gas onto the cold chip surface known as quench condensation. A corresponding electron qubit apparatus may include electrons trapped on the surface of solid hydrogen isotopes, H2, D2, and HD. The qubit apparatus may be configured as spin-qubit device based on a double-quantum dot and / or singlet-triplet qubit approach.

A quantum processing unit comprising: first qubits and second qubits arranged alternatingly, wherein each two adjacent qubits are subject to a first two-qubit interaction, wherein each qubit is adjacent to at least two qubits; a first source configured to drive the first qubits with a first Rabi frequency; a second source configured to drive the second qubits with a second Rabi frequency; and a set of mediator qubits.

The application discloses a kind of underwater magnetic field measuring devices based on diamond NV color center, comprising: diamond NV color center module, incident laser excitation module, multi-channel optical coupling module, microwave excitation module, fluorescence acquisition and photoelectric conversion module, signal processing and control module and magnetic field module;Multi-channel optical coupling module is used to divide optical fiber into multiple paths, collect the fluorescence generated by diamond block: microwave excitation module is used to switch between two single quantum resonance frequencies to drive NV color center to realize double quantum DQ reading;Signal processing and control module includes field programmable logic array chip FPGA processing unit.The application uses the double quantum DQ operating point of diamond NV color center as a measurement channel, removes the common-mode influence of D through differential measurement, significantly suppresses the D drift problem caused by temperature drift, stress and material aging from a physical point of view, so that the device can still achieve ultra-high sensitivity measurement in complex underwater environment.

One-dimensional and two-dimensional arrays of qubits are disclosed. The one-dimensional array includes two or more double-quantum dots embedded in silicon, the two or more double-quantum dots arranged in an Echelon formation, such that the distance between the two or more double-quantum dots is approximately 40 nm and the distance between the two quantum dots in each double-quantum dot is approximately 12 nm; two or more reservoirs to load electrons to the corresponding two or more double-quantum dots to form singlet-triplet qubits in each double-quantum dot; and two or more gates for controlling the formed singlet-triplet qubits. The two-dimensional array of qubits includes two or more layers of vertically-stacked one-dimensional arrays of qubits.

A circuit for reading out a state of a quantum bit 100 having a singlet spin state and a triplet spin state, comprising: a double quantum dot 101 forming the quantum bit 100, the double quantum dot 101 comprising a first quantum dot 105 and a second quantum dot 106. The circuit comprises: a cascade quantum dot 102 capacitively coupled to the second quantum dot 106; a charge reservoir 103 tunnel coupled to the cascade quantum dot 102; and a readout circuit 104 coupled to the reservoir 103. When a charge carrier tunnels between the first quantum dot 105 and the second quantum dot 106, the charge carrier tunnels between the cascade quantum dot 102 and the charge reservoir 103. A frequency source connected to a gate electrode or the charge reservoir 103 is configured to apply an alternating electrical potential 111 of a first frequency h, thereby causing a cyclic tunneling of the charge carrier only when the quantum bit is in the singlet state, which is detectable by the resonator circuit 104.

This disclosure relates to a device and method for quantum computing that utilizes a plurality of neutral atoms in an array of optical traps, where a first internal state of the neutral atoms serves as the ground state of the qubit |o>, and a second internal state serves as the excited state of the qubit |1>. According to this disclosure, a single-qubit local gate operation can be performed on a qubit comprising locally and selectively illuminating the prepared qubit in a superposition state |s> of the qubit ground state |o> and the qubit excited state |1> with a qubit-targeting laser at a first qubit-targeting laser frequency to cause a differential Stark shift for the qubit ground state |o> and the qubit excited state |1>.Furthermore, a local two-qubit gate operation can be performed on a pair of qubits comprising locally and selectively illuminating the prepared qubit pair in the qubit ground state |0> with the qubit-targeting laser at a second qubit-targeting laser frequency to couple the qubit pair to a Rydberg state |r> of the neutral atoms preferably through a third internal state c> of the neutral atoms that can serve as an intermediate state of a two-photon transition from the qubit ground state |o> to the Rydberg state |r>.