{"title":"Thin Film Materials for Room Temperature Quantum Applications","authors":"Farhana Anwar;Rafee Mahbub;Ronald A. Coutu","doi":"10.1109/TQE.2023.3322342","DOIUrl":"https://doi.org/10.1109/TQE.2023.3322342","url":null,"abstract":"Thin films with quantum defects are emerging as a potential platform for quantum applications. Quantum defects in some thin films arise due to structural imperfections, such as vacancies or impurities. These defects generate localized electronic states with unique optical and electronic properties. Crystal vacancies or defects that occur when atoms are missing from a crystal lattice can influence a material's quantum properties. In this study, we investigated inexpensive, complementary metal oxide semiconductor compatible materials with quantum defects suitable for room temperature applications. The experiments indicated 5, 15, and 17 ns relaxation times for aluminum nitride, aluminum oxide or alumina, and tin oxides, respectively. For all these materials, distinct resonant peaks are observed at approximately 1.1, 1.6, 2.2, and 2.7 GHz at room temperature (i.e., 21 °C). These peaks exhibit slight frequency shifts, corresponding to known defect locations and thin film material properties. This discovery may lead the way to reliable, cost-effective quantum applications in our daily lives.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2023-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10273435","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109157787","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Learning Circular Hidden Quantum Markov Models: A Tensor Network Approach","authors":"Mohammad Ali Javidian;Vaneet Aggarwal;Zubin Jacob","doi":"10.1109/TQE.2023.3319254","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319254","url":null,"abstract":"This article proposes circular hidden quantum Markov models (c-HQMMs), which can be applied for modeling temporal data. We show that c-HQMMs are equivalent to a tensor network (more precisely, circular local purified state) model. This equivalence enables us to provide an efficient learning model for c-HQMMs. The proposed learning approach is evaluated on six real datasets and demonstrates the advantage of c-HQMMs as compared to HQMMs and HMMs.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-11"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10269064","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109229889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samuel H. Knarr;Victor G. Bucklew;Jerrod Langston;Kevin C. Cox;Joshua C. Hill;David H. Meyer;James A. Drakes
{"title":"Spatiotemporal Multiplexed Rydberg Receiver","authors":"Samuel H. Knarr;Victor G. Bucklew;Jerrod Langston;Kevin C. Cox;Joshua C. Hill;David H. Meyer;James A. Drakes","doi":"10.1109/TQE.2023.3319270","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319270","url":null,"abstract":"Rydberg states of alkali atoms, where the outer valence electron is excited to high principal quantum numbers, have large electric dipole moments allowing them to be used as sensitive, wideband, electric field sensors. These sensors use electromagnetically induced transparency (EIT) to measure incident electric fields. The characteristic timescale necessary to establish EIT determines the effective speed at which the atoms respond to time-varying radio frequency (RF) radiation. Previous studies have predicted that this EIT relaxation rate causes a performance rolloff in EIT-based sensors beginning at an RF data symbol rate of less than 10 MHz. Here, we propose an architecture for increasing the response speed of Rydberg sensors to greater than 100 MHz, through spatiotemporal multiplexing (STM) of the probe laser. We present experimental results validating the architecture's temporal multiplexing component using a pulsed laser. We benchmark a numerical model of the sensor to these experimental data and use the model to predict the STM sensor's performance as an RF communications receiver. For an \u0000<sc>on</small>\u0000–\u0000<sc>off</small>\u0000 keyed waveform, we use the numerical model to predict bit error ratios as a function of RF power and data rates demonstrating the feasibility of error-free communications up to 100 Mb/s with an STM Rydberg sensor.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/8924785/9998549/10268327.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49981473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Learning Infused Quantum-Classical Distributed Optimization Technique for Power Generation Scheduling","authors":"Reza Mahroo;Amin Kargarian","doi":"10.1109/TQE.2023.3320872","DOIUrl":"https://doi.org/10.1109/TQE.2023.3320872","url":null,"abstract":"The advent of quantum computing can potentially revolutionize how complex problems are solved. This article proposes a two-loop quantum-classical solution algorithm for generation scheduling by infusing quantum computing, machine learning, and distributed optimization. The aim is to facilitate employing noisy near-term quantum machines with a limited number of qubits to solve practical power system optimization problems, such as generation scheduling. The outer loop is a three-block quantum alternating direction method of multipliers (QADMM) algorithm that decomposes the generation scheduling problem into three subproblems, including one quadratically unconstrained binary optimization (QUBO) and two non-QUBOs. The inner loop is a trainable quantum approximate optimization algorithm (T-QAOA) for solving QUBO on a quantum computer. The proposed T-QAOA translates interactions of quantum-classical machines as sequential information and uses a recurrent neural network to estimate variational parameters of the quantum circuit with a proper sampling technique. The T-QAOA determines the QUBO solution in a few quantum-learner iterations instead of hundreds of iterations needed for a quantum-classical solver. The outer three-block alternating direction method of multipliers coordinates QUBO and non-QUBO solutions to obtain the solution to the original problem. The conditions under which the proposed QADMM is guaranteed to converge are discussed. Two mathematical and three generation scheduling cases are studied. Analyses performed on quantum simulators and classical computers show the effectiveness of the proposed algorithm. The advantages of T-QAOA are discussed and numerically compared with QAOA, which uses a stochastic-gradient-descent-based optimizer.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-14"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10268041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109157790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Architecture for Control of Entanglement Generation Switches in Quantum Networks","authors":"Scarlett Gauthier;Gayane Vardoyan;Stephanie Wehner","doi":"10.1109/TQE.2023.3320047","DOIUrl":"10.1109/TQE.2023.3320047","url":null,"abstract":"Entanglement between quantum network nodes is often produced using intermediary devices—such as heralding stations—as a resource. When scaling quantum networks to many nodes, requiring a dedicated intermediary device for every pair of nodes introduces high costs. Here, we propose a cost-effective architecture to connect many quantum network nodes via a central quantum network hub called an entanglement generation switch (EGS). The EGS allows multiple quantum nodes to be connected at a fixed resource cost, by sharing the resources needed to make entanglement. We propose an algorithm called the rate control protocol, which moderates the level of competition for access to the hub's resources between sets of users. We proceed to prove a convergence theorem for rates yielded by the algorithm. To derive the algorithm we work in the framework of network utility maximization and make use of the theory of Lagrange multipliers and Lagrangian duality. Our EGS architecture lays the groundwork for developing control architectures compatible with other types of quantum network hubs as well as system models of greater complexity.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10265162","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135793985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Emulation of Quantum Algorithms Using CMOS Analog Circuits","authors":"Sharan Mourya;Brian R. La Cour;Bibhu Datta Sahoo","doi":"10.1109/TQE.2023.3319599","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319599","url":null,"abstract":"Quantum computers are regarded as the future of computing, as they are believed to be capable of solving extremely complex problems that are intractable on conventional digital computers. However, near-term quantum computers are prone to a plethora of noise sources that are difficult to mitigate, possibly limiting their scalability and precluding us from running any useful algorithms. Quantum emulation is an alternative approach that uses classical analog hardware to emulate the properties of superposition and entanglement, thereby mimicking quantum parallelism to attain similar speeds. By contrast, the use of classical digital hardware, such as field-programmable gate arrays (FPGAs), is less inefficient at emulating a quantum computer, as it does not take advantage of the fundamentally analog nature of quantum states. Consequently, this approach adds an inherent hardware overhead that also prevents scaling. In this work, an energy-efficient quantum emulator based on analog circuits realized in UMC 180-nm CMOS technology is proposed along with the design methodologies for a scalable computing architecture. A sixfold improvement in power consumption was observed over the FPGA-based approach for a ten-qubit emulation of Grover's search algorithm (GSA). The proposed emulator is also about 400 times faster than a Ryzen 5600x six-core processor performing a simulation of six-qubit Grover's search algorithm.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-16"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/8924785/9998549/10265215.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49981475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Initial State Encoding via Reverse Quantum Annealing and H-Gain Features","authors":"Elijah Pelofske;Georg Hahn;Hristo Djidjev","doi":"10.1109/TQE.2023.3319586","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319586","url":null,"abstract":"Quantum annealing is a specialized type of quantum computation that aims to use quantum fluctuations in order to obtain global minimum solutions of combinatorial optimization problems. Programmable D-Wave quantum annealers are available as cloud computing resources, which allow users low-level access to quantum annealing control features. In this article, we are interested in improving the quality of the solutions returned by a quantum annealer by encoding an initial state into the annealing process. We explore two D-Wave features that allow one to encode such an initial state: the reverse annealing (RA) and the h-gain (HG) features. RA aims to refine a known solution following an anneal path starting with a classical state representing a good solution, going backward to a point where a transverse field is present, and then finishing the annealing process with a forward anneal. The HG feature allows one to put a time-dependent weighting scheme on linear (\u0000<inline-formula><tex-math>$h$</tex-math></inline-formula>\u0000) biases of the Hamiltonian, and we demonstrate that this feature likewise can be used to bias the annealing to start from an initial state. We also consider a hybrid method consisting of a backward phase resembling RA and a forward phase using the HG initial state encoding. Importantly, we investigate the idea of iteratively applying RA and HG to a problem, with the goal of monotonically improving on an initial state that is not optimal. The HG encoding technique is evaluated on a variety of input problems including the edge-weighted maximum cut problem and the vertex-weighted maximum clique problem, demonstrating that the HG technique is a viable alternative to RA for some problems. We also investigate how the iterative procedures perform for both RA and HG initial state encodings on random whole-chip spin glasses with the native hardware connectivity of the D-Wave Chimera and Pegasus chips.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-21"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10265106","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109157791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Private Product Computation Using Quantum Entanglement","authors":"René Bødker Christensen;Petar Popovski","doi":"10.1109/TQE.2023.3320052","DOIUrl":"https://doi.org/10.1109/TQE.2023.3320052","url":null,"abstract":"In this article, we show that a pair of entangled qubits can be used to compute a product privately. More precisely, two participants with a private input from a finite field can perform local operations on a shared, Bell-like quantum state, and when these qubits are later sent to a third participant, the third participant can determine the product of the inputs, but without learning more about the individual inputs. We give a concrete way to realize this product computation for arbitrary finite fields of prime order.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/iel7/8924785/9998549/10265118.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49981486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shu Lok Tsang;Maxwell T. West;Sarah M. Erfani;Muhammad Usman
{"title":"Hybrid Quantum–Classical Generative Adversarial Network for High-Resolution Image Generation","authors":"Shu Lok Tsang;Maxwell T. West;Sarah M. Erfani;Muhammad Usman","doi":"10.1109/TQE.2023.3319319","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319319","url":null,"abstract":"Quantum machine learning (QML) has received increasing attention due to its potential to outperform classical machine learning methods in problems, such as classification and identification tasks. A subclass of QML methods is quantum generative adversarial networks (QGANs), which have been studied as a quantum counterpart of classical GANs widely used in image manipulation and generation tasks. The existing work on QGANs is still limited to small-scale proof-of-concept examples based on images with significant downscaling. Here, we integrate classical and quantum techniques to propose a new hybrid quantum–classical GAN framework. We demonstrate its superior learning capabilities over existing quantum techniques by generating \u0000<inline-formula><tex-math>$28 times 28$</tex-math></inline-formula>\u0000 pixels grayscale images without dimensionality reduction or classical pre/postprocessing on multiple classes of the standard Modified National Institute of Standards and Technology (MNIST) and Fashion MNIST datasets, which achieves comparable results to classical frameworks with three orders of magnitude less trainable generator parameters. To gain further insight into the working of our hybrid approach, we systematically explore the impact of its parameter space by varying the number of qubits, the size of image patches, the number of layers in the generator, the shape of the patches, and the choice of prior distribution. Our results show that increasing the quantum generator size generally improves the learning capability of the network. The developed framework provides a foundation for future design of QGANs with optimal parameter set tailored for complex image generation tasks.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10264175","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109157789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Shor's Algorithm Using Efficient Approximate Quantum Fourier Transform","authors":"Kento Oonishi;Noboru Kunihiro","doi":"10.1109/TQE.2023.3319044","DOIUrl":"https://doi.org/10.1109/TQE.2023.3319044","url":null,"abstract":"Shor's algorithm solves the integer factoring and discrete logarithm problems in polynomial time. Therefore, the evaluation of Shor's algorithm is essential for evaluating the security of currently used public-key cryptosystems because the integer factoring and discrete logarithm problems are crucial for the security of these cryptosystems. In this article, a new approximate quantum Fourier transform is proposed, and it is applied to Rines and Chuang's implementation. The proposed implementation requires one-third the number of \u0000<inline-formula><tex-math>$T$</tex-math></inline-formula>\u0000 gates of the original. Moreover, it requires one-fourth of the \u0000<inline-formula><tex-math>$T$</tex-math></inline-formula>\u0000-depth of the original. Finally, a \u0000<inline-formula><tex-math>$T$</tex-math></inline-formula>\u0000-scheduling method for running the circuit with the smallest KQ (where K is the number of logical qubits and Q is the circuit depth) is presented.","PeriodicalId":100644,"journal":{"name":"IEEE Transactions on Quantum Engineering","volume":"4 ","pages":"1-16"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10262370","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"109157792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}