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Diabetes is a metabolic disorder characterized by blood glucose levels above normal limits. Diabetes occurs when the body is unable to produce sufficient insulin to regulate blood sugar levels. As a result, blood sugar management becomes impaired and there is no cure for diabetes. Early detection of diabetes provides an opportunity to delay or prevent its progression into acute stages. Clustering can help identify patterns and groups of diabetes symptoms by analyzing attributes that indicate these symptoms. In this study, researchers are using K-Medoid and Quantum K-Medoid methods for clustering diabetes data. Quantum computing utilizes quantum bits, or qubits, which can represent multiple states at the same time. Compared to classical computers, quantum computing has the potential for an exponential speedup in problem-solving. Researchers conducted a comparison between two methods: the classic K-Medoids method and the K-Medoids method utilizing quantum computing. The researchers found that both Quantum K-Medoid and Classic K-Medoid achieved the same clustering accuracy of 91%. In testing with the Quantum K-Medoids algorithm, it was found that the cost value in the 8th epoch showed a significant decrease compared to the Classical K-Medoids algorithm. This demonstrates that Quantum K-Medoid can be considered a viable alternative for clustering purposes.

The fundamental problem in this research is to explore a more profound understanding regarding both performance and efficiency in quantity computing. Successful implementation of algorithms in computational computing environments can unlock the potential for significant improvements in information processing and neural network modelling. This research focuses on developing the Madaline and Perceptron algorithm using a quantum approach. This study compares the two algorithms regarding the accuracy and epoch of the test results. The dataset used in this study is using a lens dataset. There are four attributes: 1) patient age: young, pre-presbyopia, presbyopia 2) eyeglass prescription: myopia, hypermetropia 3) astigmatic: no, yes. 4) tear production rate: reduced, normal. There are three classes: 1) patients must have hard contact lenses installed, 2) patients must have soft contact lenses installed, and 3) patients cannot have contact lenses installed. The number of data is 24 data. The result of this research is the development of the Madaline and Perceptron algorithms with a quantum computing approach. Comparing these algorithms shows the best accuracy is the Perceptron algorithm, namely 100%. In comparison, Madaline is 62.5%, and the smallest epoch is the Madaline algorithm, namely 4 epochs, while the smallest Perceptron epoch is 317. This research significantly contributes to developing computing and neural networks, with potential applications extending from data processing to more accurate modelling in artificial intelligence, data analysis and understanding complex patterns.

In order to solve the problem that the scheduling length of existing scheduling algorithms in heterogeneous signal processing platforms is large, which leads to the decline of real-time performance of signal processing applications, a quantum scheduling algorithm for heterogeneous signal processing platforms is proposed. The algorithm adopts task priority diffluence sorting strategy to obtain more accurate task scheduling order. Quantum bits are used to encode the task allocation scheme, which increases the diversity of the task allocation scheme, and the coding rules help to find the global optimal solution out of the local optimal. According to the principle of minimum computing cost and the idea of task replication, the processor is allocated to reduce the communication cost between tasks, and the quantum coding scheme is updated through the quantum turnstile to constantly approximate the optimal solution. Simulation results show that the proposed algorithm can reduce the scheduling length, improve the real-time performance of signal processing applications, and improve the working efficiency of the platform. [ABSTRACT FROM AUTHOR]

The emergence of information metamaterials has spurred significant advances in the field of information sciences. However, the current studies are predominantly focused on classical bits as the fundamental information units, and the classical bit can only be located at two poles of Bloch sphere, resulting in limited information capacity. To break such limit, quantum bits (qubits) offer a promising solution since they have superposition states anywhere on the Bloch sphere. Here, a Pancharatnam‐Berry (PB) phase metasurface is used to emulate the qubits. Firstly, it proposes a theoretical concept of analog quantum bit and develops its mathematical and geometrical representations. Subsequently, a meta‐atom is designed as a physical platform to implement the concept of analog qubits. By manipulating the geometric configuration of the proposed meta‐atom, it achieves arbitrary superpositions of polarization states. A PB phase metasurface is experimentally fabricated to validate that the proposed analog qubit can be used to emulate the quantum bit in terms of both mathematical and geometrical representations. This work not only provides a theoretical foundation to go beyond the information limit of classical bits but also develops a feasible physics platform to investigate quantum information metasurfaces, which would complement and revolutionize classical information science. [ABSTRACT FROM AUTHOR]

• The variability of silicon-based quantum dot device has been studied for realizing large-scale quantum bit arrays. • Influences of work function variation (WFV) were examined focusing on fin-shaped silicon quantum dot device with a multi-gate configuration. • Threshold voltage (V th) of the gate stack is affected by work function variation from gates not targeted for the operation (surrounding gates). • Positive bias on the surrounding gate can improve the accuracy of the V th evaluation. • The energy level of the silicon channel can be discussed with high accuracy even under the existence of WFV in the multi-gate. We explored the effects of gate work function variation (WFV) through device simulation on a fin-shaped silicon quantum dot device with a multi-gate configuration for a large-scale integrated array. The threshold voltage (V th) of current–voltage characteristics is affected by WFV in both main and surrounding gates, indicating the existence of electrostatic coupling among these gates. The electrostatic coupling can be reduced by biasing on the surrounding gates. Furthermore, the concept of V th , following conventional transistors, works as a reference of voltage and potential in the present multi-gate device. This knowledge contributes to establishing a practical method for the statistical analysis of qubit variability. [ABSTRACT FROM AUTHOR]

The utilisation of quantum properties can largely impact how technological devices work. Up to date, the acquired knowledge of the quantum nature of several systems inspired the proposal of several novel technologies such as quantum sensing, quantum simulation and quantum computing. Single Molecule Magnets (SMMs) represent a class of quantum objects with promising properties to be exploited in quantum technologies. As of today, SMMs have been shown to possess bewildering quantum effects such as Quantum Tunnelling of the Magnetisation (QTM), quantisation of the energy manifold, coherence, spin parity effects and entanglement, among others. Furthermore, they have been successfully integrated into hybrid single-molecule spintronic devices, such as spin transistors and spin valves, hence, propitiating extensive investigation of technological applications. In this Review Article, some key quantum aspects, which make SMMs promising systems for technological proposals, are revised. Moreover, single-molecule devices, in which SMMs have been integrated in hybrid devices, as well as the technological applications such as quantum sensing, quantum simulation and quantum computing are described.

The utilisation of quantum properties can largely impact how technological devices work. Up to date, the acquired knowledge of the quantum nature of several systems inspired the proposal of several novel technologies such as quantum sensing, quantum simulation and quantum computing. Single Molecule Magnets (SMMs) represent a class of quantum objects with promising properties to be exploited in quantum technologies. As of today, SMMs have been shown to possess bewildering quantum effects such as Quantum Tunnelling of the Magnetisation (QTM), quantisation of the energy manifold, coherence, spin parity effects and entanglement, among others. Furthermore, they have been successfully integrated into hybrid single-molecule spintronic devices, such as spin transistors and spin valves, hence, propitiating extensive investigation of technological applications. In this Review Article, some key quantum aspects, which make SMMs promising systems for technological proposals, are revised. Moreover, single-molecule devices, in which SMMs have been integrated in hybrid devices, as well as the technological applications such as quantum sensing, quantum simulation and quantum computing are described.

In quantum computing, calculations are achieved using quantum mechanics. Typically, two main phenomena of quantum mechanics (i.e., superposition and entanglement) allow quantum computing to solve some problems more efficiently than classical algorithms. The most well-known advantage of quantum computing is the speedup of some of the calculations, which have been performed before by classical applications. Scientists and engineers are attempting to use quantum computing in different fields of science, e.g., drug discovery, chemistry, computer science, etc. However, there are few attempts to use quantum computing in power and energy applications. This paper tries to highlight this gap by discussing one of the most famous quantum computing algorithms (i.e., Grover's algorithm) and discussing the potential applications of this algorithm in power and energy systems, which can serve as one of the starting points for using Grover's algorithm in power and energy systems. [ABSTRACT FROM AUTHOR]

Research related to the free-space quantum information transfer is very important now. Entanglement of quantum bits ensures absolute security of data transmission. We study the ability of an atmospheric quantum channel to preserve the entanglement during the transmission of information encoded by the modes of the Gaussian beam. The operator approach is used. Namely, we estimate the quality of the entanglement transmission by finding the distance between the transformation matrix of the quantum channel and the subspace of matrices being tensor products of matrices corresponding to disentangled qubits. The technique is related to singular expansions for matrices. Teleportation algorithm is considered. [ABSTRACT FROM AUTHOR]

The evolution of quantum computers and quantum machine learning (QML) algorithms have started demonstrating exponential speed-ups. In machine learning problems, the efficient handling and manipulation of linear algebra subroutines defines the complexity of the task to be performed. Quantum computers handle big datasets in the form of vectors and matrix operations very efficiently. In this paper, quantum support vector machine (QSVM) algorithm is used to solve a classification problem using a benchmarking MNIST dataset of handwritten images of digits. Quantum SVM variational and kernel matrix algorithms are implemented to analyze quantum speedup on quantum simulator and physical quantum processor back-ends. The study compared classical and quantum SVM algorithms in terms of execution time and accuracy. The results explicitly prove quantum speed-up achieved by quantum classifiers on quantum back-ends for machine learning applications. [ABSTRACT FROM AUTHOR]

In order to control the state of a two-level quantum system (e.g. the spin state of an ion qubit), optical frequency combs perform a two-photon stimulated Raman process through stimulated absorption from one comb tooth and stimulated emission into another comb tooth. If the two-level energy gap is an integer multiple of the repetition rate of the laser, resonant Rabi oscillations are excited. When these latter have a frequency close to the qubit’s transition one, a strongly anharmonic phase-locked cycle may exist on the Bloch sphere, which generates a sub-harmonic series of very narrow, equally spaced, spectral lines. If the repetition rate of an optical frequency comb is appropriately tuned to these latter (up to the average carrier envelope frequency), a highly resonant dynamical regime of the two-level system should be reached where the Raman stimulated absorption and emission processes would occur for any pair of adjacent comb teeth.

The single-bit quantum information perfect transfer determined only by the dynamic evolution of the system in a spin chain is investigated. Our results show that the quantum control of the above quantum information perfect transfer can be achieved by applying a low-intensity symmetric magnetic field to the spin chain. We have studied the influence of the magnetic field on the perfect transfer of quantum information in the arbitrary-length spin chain. It gives that the time of the quantum information perfect transfer is determined by applying the low-intensity magnetic field which is symmetric about the spin chain and whose difference value is constant between the closed lattices in the spin chain. Furthermore, we put forward a scheme to achieve the quantum control of quantum information perfect transfer in the arbitrarily-length spin chain by applying the magnetic field. [ABSTRACT FROM AUTHOR]

Over the last two decades, tremendous advances have been made for constructing large-scale quantum computers. In particular, quantum computing platforms based on superconducting qubits have become the leading candidate for scalable quantum processor architecture, and the milestone of demonstrating quantum supremacy has been first achieved using 53 superconducting qubits in 2019. In this study, we provide a brief review on the experimental efforts towards the large-scale superconducting quantum computer, including qubit design, quantum control, readout techniques, and the implementations of error correction and quantum algorithms. Besides the state of the art, we finally discuss future perspectives, and which we hope will motivate further research. [ABSTRACT FROM AUTHOR]

This paper proposes a new quantum-inspired evolutionary algorithm for solving ordering problems. Quantum-inspired evolutionary algorithms based on binary and real representations have been previously developed to solve combinatorial and numerical optimization problems, providing better results than classical genetic algorithms with less computational effort. However, for ordering problems, order-based genetic algorithms are more suitable than those with binary and real representations. This is because specialized crossover and mutation processes are employed to always generate feasible solutions. Therefore, this work proposes a new quantum-inspired evolutionary algorithm especially devised for ordering problems (QIEA-O). Two versions of the algorithm have been proposed. The so-called pure version generates solutions by using the proposed procedure alone. The hybrid approach, on the other hand, combines the pure version with a traditional order-based genetic algorithm. The proposed quantum-inspired order-based evolutionary algorithms have been evaluated for two well-known benchmark applications – the traveling salesman problem (TSP) and the vehicle routing problem (VRP) – as well as in a real problem of line scheduling. Numerical results were obtained for ten cases (7 VRP and 3 TSP) with sizes ranging from 33 to 101 stops and 1 to 10 vehicles, where the proposed quantum-inspired order-based genetic algorithm has outperformed a traditional order-based genetic algorithm in most experiments. [ABSTRACT FROM AUTHOR]

Multi-objective combinatorial optimization (MOCO) is an essential concern for the implementation of large-scale distributed modeling and simulation (MS) system. It is more complex than general computing systems, with higher dynamics and stricter demands on real-time performance. The quality and speed of the optimal decision directly decides the efficiency of the simulation. However, few works have been carried out for multi-objective combinatorial optimization MOCO especially in large-scale and service-oriented distributed simulation systems (SoDSSs). The existing algorithms for MOCO in SoDSSs are far from enough owing to their low accuracy or long decision time. To overcome this bottleneck, in this paper, a quantum multi-agent evolutionary algorithm (QMAEA), for addressing MOCO in large-scale SoDSSs is proposed. In QMAEA, the concept and characteristics of agent and quantum encoding are introduced for high intelligent searching. Each agent represented by a quantum bit, called a quantum agent (QAgent), is defined as a candidate solution for a MOCO problem, and each QAgent is assigned an energy, which denotes the fitness or objective function value of the candidate solution represented by it. Each QAgent is connected by four other QAgents nearby, and all QAgents are organized by an annular grid, called a multi-agent grid (MAG). In a MAG system, the population of QAgents can reproduce, perish, compete for survival, observe and communicate with the environment, and make all their decisions autonomously. Several operators, i.e. energy-evaluation-operator, competition-operator, crossover-operator, mutation-operator and trimming-operator, are designed to specify the evolvement of the MAG. The theory of predatory search strategy of animals is introduced in the evolution of QMAEA. Multiple evolutionary strategies, such as local-evolution-strategy, local-mutation-strategy and global-mutation-strategy are designed and used to balance the exploration (global search ability) and the exploitation (local search ability) of QMAEA. The framework and procedures of QMAEA are presented in detail. The simulation and comparison results demonstrate the proposed method is very effective and efficient for addressing MOCO in SoDSSs. [ABSTRACT FROM AUTHOR]

We considered the phase of the quantum bit wave function as a resource for storage and transmission of classical information. We qualitatively evaluated the effectiveness of this resource. We considered use of this resource for the transmission of classical information through a quantum channel of communication with the help of technology of quantum teleportation. [ABSTRACT FROM AUTHOR]

Combating the detrimental effects of noise remains a major challenge in realizing a scalable quantum computer. To help to address this challenge, we introduce a model realizing a controllable qubit-bath coupling using a sequence of LC resonators. The model establishes a strong coupling to a low-temperature environment which enables us to lower the effective qubit temperature making ground state initialization more efficient. The operating principle is similar to that of a recently proposed coplanar-waveguide cavity (CPW) system, for which our work introduces a complementary and convenient experimental realization. The lumped-element model utilized here provides an easily accessible theoretical description. We present analytical solutions for some experimentally feasible parameter regimes and study the control mechanism. Finally, we introduce a mapping between our model and the recent CPW system. [ABSTRACT FROM AUTHOR]

The aim of this paper is to guide computer scientists through the barriers that separate quantum computing from conventional computing. We introduce basic principles of quantum mechanics to explain where the power of quantum computers comes from and why it is difficult to harness. We describe the diffrences between classical and quantum computers, bit and quantum bit and quantum key distribution. [ABSTRACT FROM AUTHOR]

Abstract: In order to control the state of qubits by a microwave pulse, the irradiation time and the amplitude have to be controlled precisely. We have developed a single-flux-quantum (SFQ) microwave chopper for high-speed switching of microwave pulses. The proposed chopper is composed of a DC/SFQ convertor, an SFQ switch, a PTL driver, and a superconducting low-pass filter (LPF). The chopper converts an input microwave, which is generated by an external microwave generator at the room temperature, into microwave pulses by using start/stop SFQ control signals. We designed and implemented a microwave chopper module, which can be attached to dilution refrigerators. SFQ chips were fabricated using the ISTEC 2.5 kA/cm2 Nb process. We tested the microwave chopper module at 4.2K, and demonstrated that a 5-GHz microwave whose amplitude ranging from 0μV to 150μV can be chopped by the SFQ control signals. [Copyright &y& Elsevier]

Abstract: Ferromagnetic-insulator (FI) based Josephson junctions are promising candidates for a coherent superconducting quantum bit as well as a classical superconducting logic circuit. Recently the appearance of an intriguing atomic-scale transition has been theoretically predicted. In order to uncover the mechanism of this phenomena, we numerically calculate the spectrum of Andreev bound states in a FI barrier by diagonalizing the Bogoliubov–de Gennes equation. We show that Andreev spectrum drastically depends on the parity of the FI-layer number L and accordingly the state is always more stable than the 0 () state if L is odd (even). [Copyright &y& Elsevier]

We have demonstrated that light is confined in a single mode near a very small defect (such as an impurity atom) embedded in photonic crystals by coherent control using a dark line that is a spectrum singularity leading to the complete quenching of emission. In this demonstration, we have clarified the strong confinement and a very short response time, as compared with the widely used tunable PBG method. These features are useful for keeping the memory in a two-state quantum system such as a quantum bit (qubit) and for processing quantum information. [ABSTRACT FROM AUTHOR]

Abstract: We review the use of mechanical oscillators in circuit quantum electrodynamics. The capacitive coupling of nano-electromechanical systems with quantum bits and superconducting microwave resonators gives rise to a rich quantum physics involving electrons, photons and phonons. We focus in particular on the linear coupling between a mechanical oscillator and a microwave resonator and present the quantum dynamics that stems from the phonotonic Josephson junction. The microwave cavity turns out to be a powerful device to detect quantum phonon states and manipulate entangled states between phonons and photons. [Copyright &y& Elsevier]

Abstract: We have been studying a superconducting quantum-computing system where superconducting Josephson-junction quantum bits (qubits) are controlled and read out by rapid single-flux-quantum (RSFQ) circuits. In this study, we designed and fabricated an on-chip RSFQ microwave pulse generator (MPG), which generates microwave pulses with the time resolution of sub-ns for precise control of qubit states. The output microwave amplitude of the MPG can be amplified to more than 350μV using a multi-flux-quantum (MFQ) driver, which increases the number of the propagating single-flux-quantum (SFQ) pulses. Fundamental properties of the MFQ driver and the RSFQ MPG were measured at 4.2K. It was confirmed that the MFQ driver can amplify an SFQ pulse up to six MFQ pulses and the irradiation time and the amplitude of the output microwave of the RSFQ MPG can be controlled adequately. [ABSTRACT FROM AUTHOR]

Abstract: We study the Josephson transport through ferromagnetic insulators (FIs) by taking into account its band structure explicitly. In the case of the fully polarized FIs (FPFIs), we found the formation of a and an atomic-scale transition induced by increasing the FI thickness. More remarkably, in the Josephson junction through spin-filter materials such as Eu chalcogenides, the orbital hybridization between the conduction d and the localized f electron gives rise to the behavior. Such FI-based can be used to implement highly coherent solid-state quantum bits. [Copyright &y& Elsevier]

A quantum-inspired evolutionary algorithm (QEA) is proposed as a stochastic algorithm to perform combinatorial optimization problems. The QEA is evolutionary computation that uses quantum bits and superposition states in quantum computation. Although the QEA is a coarse-grained parallel algorithm, it involves many parameters that must be adjusted manually. This paper proposes a new method, named pair swap, which exchanges each best solution information between two individuals instead of migration in the QEA. Experimental results show that our proposed method is a simpler algorithm and can find a high quality solution in the 0-1 knapsack problem. [ABSTRACT FROM AUTHOR]

Abstract: We report on the fabrication and simulation of a lateral quantum dot (QD) designed for coherent electrical manipulation and readout of a two-level spin-charge system. The two-level system involves a slight hybridization of a single electron spin to the QD orbitals. A permanent magnet integrated with high-frequency electrode produces a static slanting magnetic field suitable for voltage controlled single qubit rotations. Resonance frequency and rotation speed are related to device parameters. Response of the nearby quantum point contact charge sensor is modeled for continuous microwave excitation, taking into account parasitic photon-assisted tunneling effects induced by the high-frequency electric field. The model predicts a well-defined resonance in the readout signal associated to driven rotations of the qubit states. [Copyright &y& Elsevier]

The proof of the no-go theorem of unconditionally secure quantum bit commitment depends crucially on the assumption that Alice knows every detail of the protocol so that no secret parameters exist. In this paper we show that, for the perfectly concealing case, it is possible to establish the no-go theorem without making this assumption. [ABSTRACT FROM AUTHOR]

A single-flux-quantum (SFQ) circuit is thought to be very suitable as a peripheral circuit for superconducting quantum bits (qubits), which can manipulate and detect the qubit state at a temperature state similar to qubits. Even though the power consumption of SFQ circuits is extremely small, it is still sufficient to heat the substrate at a temperature below 1 K. We have investigated and demonstrated low-power SFQ circuits for this application, using the LR-loading technique, which can reduce the static power consumption of the SFQ circuits. Simulation results show that the ratio of the switching speed to the time constant of the bias circuit is important for the stable operation of low-power SFQ circuits. The static power consumption of SFQ circuits can be reduced to the same order as the dynamic power consumption through optimization of the circuit parameters. We have designed and tested a low-power SFQ clock generator using the LR-loading technique and confirmed its stable operation at 4.2 K, where the power consumption is reduced by 93% compared with ordinary biased circuits. [ABSTRACT FROM AUTHOR]

A microwave chopper using single-flux-quantum (SFQ) circuits is proposed for the control of quantum bits (qubits). The proposed microwave chopper is composed of a DC/SFQ converter, an SFQ switch and a band-pass filter (BPF). In operation, an externally applied microwave is input to a DC/SFQ converter to generate an SFQ pulse train, which is chopped at high speed by the SFQ switch. The SFQ pulse train is then filtered by the BPF to remove higher harmonics. The transient response, the amplitude and the spectrum of the microwave output from the chopper were examined by circuit simulation, taking into account the thermal noise. The chopper was implemented using the SRL 2.5 kA/cm2 Nb standard process and its characteristics were investigated. It was shown that the microwave output could be successfully chopped by the SFQ switch. The amplitude and line width of the microwave output were measured as 15 μV and 2 Hz at 7 GHz. [ABSTRACT FROM AUTHOR]