Download or read book Error Characterization and Quantum Control Benchmarking in Liquid State NMR Using Quantum Information Processing Techniques written by Martin Laforest and published by . This book was released on 2008 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum information processing has been the subject of countless discoveries since the early 1990's. It is believed to be the way of the future for computation: using quantum systems permits one to perform computation exponentially faster than on a regular classical computer. Unfortunately, quantum systems that not isolated do not behave well. They tend to lose their quantum nature due to the presence of the environment. If key information is known about the noise present in the system, methods such as quantum error correction have been developed in order to reduce the errors introduced by the environment during a given quantum computation. In order to harness the quantum world and implement the theoretical ideas of quantum information processing and quantum error correction, it is imperative to understand and quantify the noise present in the quantum processor and benchmark the quality of the control over the qubits. Usual techniques to estimate the noise or the control are based on quantum process tomography (QPT), which, unfortunately, demands an exponential amount of resources. This thesis presents work towards the characterization of noisy processes in an efficient manner. The protocols are developed from a purely abstract setting with no system-dependent variables. To circumvent the exponential nature of quantum process tomography, three different efficient protocols are proposed and experimentally verified. The first protocol uses the idea of quantum error correction to extract relevant parameters about a given noise model, namely the correlation between the dephasing of two qubits. Following that is a protocol using randomization and symmetrization to extract the probability that a given number of qubits are simultaneously corrupted in a quantum memory, regardless of the specifics of the error and which qubits are affected. Finally, a last protocol, still using randomization ideas, is developed to estimate the average fidelity per computational gates for single and multi qubit systems. Even though liquid state NMR is argued to be unsuitable for scalable quantum information processing, it remains the best test-bed system to experimentally implement, verify and develop protocols aimed at increasing the control over general quantum information processors. For this reason, all the protocols described in this thesis have been implemented in liquid state NMR, which then led to further development of control and analysis techniques.
Download or read book Experimental Quantum Computation and Information written by F. de Martini and published by IOS Press. This book was released on 2003-02-12 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Fermi Summer School of Physics on "Experimental Quantum Information and Computing" represents a primer on one of the most intriguing and rapidly expanding new areas of physics. In this part, the interest in quantum information (QI) science is due to the discovery that a computer operating on quantum mechanical principles can solve certain important computational problems exponentially faster than any conceivable classical computer. But this interest is also due to the interdisciplinary nature of the field: the rapid growth is attributable, in part, to the stimulating confluence of researchers and ideas from physics, chemistry, mathematics, information theory, and computer science. Physics plays a paramount role in QI science, as we realize that computing is itself a physical process subject to physical laws. The incredible growth of classical computers and information processors in the 20th century stems from Turing's notion that a computer is independent of the physical device actually being used; be they relays, vacuum tubes, or semiconductor transistors. As we strive to build useful quantum information processors into the 21st century, we thus look for any physical system that obeys the laws of quantum mechanics, from single photons and atoms to quantum superconducting devices. These Fermi lectures take us on a journey through these and other promising current experimental candidates for QI processing, spanning quantum optics and laser physics, atomic and molecular physics, physical chemistry, and condensed-matter physics. While this broad coverage of experimental physics represents a challenge to the student, such an appreciation of these fields will be critical in the future success of quantum technology. Indeed, the most exciting feature of QI science is that the technology ultimately leading to a quantum processor is likely presently unknown.
Download or read book Liquid Crystal State Nmr Quantum Computing Characterization Control and Certification written by Denis-Alexandre Trottier and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum computers offer the possibility of solving some problems more efficiently than their classical counterparts. The current forerunner in the experimental demonstration of quantum algorithms is Nuclear Magnetic Resonance (NMR). Known for its implementations at liquid state, NMR quantum computing consists of computing on nuclear spins. In the liquid crystal state, dipolar couplings are available, offering an increased clock frequency and a faster recycling of algorithms. Here investigated is the cost at which this comes, namely, a more complicated internal Hamiltonian, making the system harder to characterize and harder to control. In this thesis I present new methods for characterizing the Hamiltonian of dipolar coupled spin systems, and I report experimental results of characterizing an oriented 6-spin system. I then present methods and results concerning the quantum optimal control of this same spin system. Finally, I present experiments and simulations regarding the certification of computational quantum gates implemented in that same dipolar coupled spin system.
Download or read book Ensemble Quantum Computing by Liquid State NMR Spectroscopy written by and published by . This book was released on 2001 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goals of this project were to use liquid-state nuclear magnetic resonance (NMR) as a testbed for developing general methods of solving computational problems on ensemble quantum computers, to study the fundamental physics and computer science behind such machines, and to learn how to make optimal use of the trade-offs that their unique capabilities permit us to make. During the three years of this project, we have: (1) developed a library of radio-frequency pulse sequences which allow a rich repertoire of unitary 'quantum logic gates' to be implemented by NMR; (2) designed general methods, based on magnetic field gradients, for preparing the 'pseudopure' states needed for quantum computing by liquid-state NMR; (3) invented procedures, based on gradients combined with molecular diffusion by which a wide variety of decoherent processes can be implemented using NMR; (4) used these procedures to perform the first demonstrations of quantum error correction as well as decoherence-free subspaces I systems; and (5) used the average Hamiltonian techniques developed many years ago by John Waugh at MIT to implement the first simulations of one quantum system by another, as originally proposed by Richard Feynman. Many of the techniques we have developed in the course of this work promise to be highly useful in other approaches to quantum computing, both by our group as well as many others.
Download or read book Quantum Logic Gate Construction and Quantum Algorithms written by Xinlan Zhou and published by . This book was released on 2002 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Implementation of Hybrid Codes and Nuclear Magnetic Resonance Quantum Information Processing written by Shayan Majidy and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of quantum error correcting techniques is of paramount importance to the ultimate goal of implementing practical quantum computers. The simultaneous transmission of quantum and classical information over a quantum channel was initially investigated by Shor and since been continued by others. It was shown that there is an advantage to transmitting both quantum and classical information simultaneously, compared to independent transmissions. The characterization and construction of codes that allow to transmit both quantum and classical information, which we refer to as hybrid codes, was done from a coding theory perspective and by using the operator algebra quantum error correction (OAQEC) perspective. In this work we unify these two perspectives, showing that the coding theory formulation is a specific case of the OAQEC perspective. As a result we generalized the quantum hamming bound to the hybrid case. To date no such hybrid codes have been physically implemented. Nuclear magnetic resonance (NMR) quantum information processors (QIP) have been an excellent test bed for quantum computing. The techniques of NMR had been refined for many years and can now be applied to quantum computing. NMR techniques provides a high degree of qubit control and long decoherence times compared to other QIP. These two properties of NMR QIP make it a prime candidate for implementing hybrid codes. In this work we developed a hybrid code and designed the circuit for encoding it. We used Matlab to simulate the pulse sequence which would be used in an NMR QIP to carry out the encoding of the hybrid circuit. According to those simulations the full encoding, a single qubit Pauli error and a full decoding can be carried out without the effects of decoherence destroying the quantum information beyond retrieval.
Download or read book The Journal of Chemical Physics written by and published by . This book was released on 2003 with total page 1152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Information Science and Technology in a Quantum World written by and published by . This book was released on 2002 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1976 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum State Transfer and Network Engineering written by Georgios M. Nikolopoulos and published by Springer Science & Business Media. This book was released on 2013-10-05 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Faithful communication is a necessary precondition for large-scale quantum information processing and networking, irrespective of the physical platform. Thus, the problems of quantum-state transfer and quantum-network engineering have attracted enormous interest over the last years, and constitute one of the most active areas of research in quantum information processing. The present volume introduces the reader to fundamental concepts and various aspects of this exciting research area, including links to other related areas and problems. The implementation of state-transfer schemes and the engineering of quantum networks are discussed in the framework of various quantum optical and condensed matter systems, emphasizing the interdisciplinary character of the research area. Each chapter is a review of theoretical or experimental achievements on a particular topic, written by leading scientists in the field. The volume aims at both newcomers as well as experienced researchers.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Optical Magnetometry written by Dmitry Budker and published by Cambridge University Press. This book was released on 2013-03-07 with total page 431 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive coverage of the principles, technology and diverse applications of optical magnetometry for graduate students and researchers in atomic physics.
Download or read book Lectures on Quantum Information written by Dagmar Bruss and published by Wiley-VCH. This book was released on 2007 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum Information Processing is a young and rapidly growing field of research at the intersection of physics, mathematics, and computer science. Its ultimate goal is to harness quantum physics to conceive -- and ultimately build -- "quantum" computers that would dramatically overtake the capabilities of today's "classical" computers. One example of the power of a quantum computer is its ability to efficiently find the prime factors of a larger integer, thus shaking the supposedly secure foundations of standard encryption schemes. This comprehensive textbook on the rapidly advancing field introduces readers to the fundamental concepts of information theory and quantum entanglement, taking into account the current state of research and development. It thus covers all current concepts in quantum computing, both theoretical and experimental, before moving on to the latest implementations of quantum computing and communication protocols. With its series of exercises, this is ideal reading for students and lecturers in physics and informatics, as well as experimental and theoretical physicists, and physicists in industry. Dagmar Bruß graduated at RWTH University Aachen, Germany, and received her PhD in theoretical particle physics from the University of Heidelberg in 1994. As a research fellow at the University of Oxford she started to work in quantum information theory. Another fellowship at ISI Torino, Italy, followed. While being a research assistant at the University of Hannover she completed her habilitation. Since 2004 Professor Bruß has been holding a chair at the Institute of Theoretical Physics at the Heinrich-Heine-University Düsseldorf, Germany. Gerd Leuchs studied physics and mathematics at the University of Cologne, Germany, and received his Ph.D. in 1978. After two research visits at the University of Colorado in Boulder, USA, he headed the German gravitational wave detection group from 1985 to 1989. He became technical director at Nanomach AG in Switzerland. Since 1994 Professor Leuchs has been holding the chair for optics at the Friedrich-Alexander-University of Erlangen-Nuremberg, Germany. His fields of research span the range from modern aspects of classical optics to quantum optics and quantum information. Since 2003 he has been Director of the Max Planck Research Group for Optics, Information and Photonics at Erlangen.
Download or read book Quantum Computing written by Mikio Nakahara and published by CRC Press. This book was released on 2008-03-11 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covering both theory and progressive experiments, Quantum Computing: From Linear Algebra to Physical Realizations explains how and why superposition and entanglement provide the enormous computational power in quantum computing. This self-contained, classroom-tested book is divided into two sections, with the first devoted to the theoretical aspect
Download or read book Quantum Computing written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2019-04-27 with total page 273 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum mechanics, the subfield of physics that describes the behavior of very small (quantum) particles, provides the basis for a new paradigm of computing. First proposed in the 1980s as a way to improve computational modeling of quantum systems, the field of quantum computing has recently garnered significant attention due to progress in building small-scale devices. However, significant technical advances will be required before a large-scale, practical quantum computer can be achieved. Quantum Computing: Progress and Prospects provides an introduction to the field, including the unique characteristics and constraints of the technology, and assesses the feasibility and implications of creating a functional quantum computer capable of addressing real-world problems. This report considers hardware and software requirements, quantum algorithms, drivers of advances in quantum computing and quantum devices, benchmarks associated with relevant use cases, the time and resources required, and how to assess the probability of success.
Download or read book Will We Ever Have a Quantum Computer written by Mikhail I. Dyakonov and published by Springer Nature. This book was released on 2020-03-23 with total page 49 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses a broad community of physicists, engineers, computer scientists and industry professionals, as well as the general public, who are aware of the unprecedented media hype surrounding the supposedly imminent new era of quantum computing. The central argument of this book is that the feasibility of quantum computing in the physical world is extremely doubtful. The hypothetical quantum computer is not simply a quantum variant of the conventional digital computer, but rather a quantum extension of a classical analog computer operating with continuous parameters. In order to have a useful machine, the number of continuous parameters to control would have to be of such an astronomically large magnitude as to render the endeavor virtually infeasible. This viewpoint is based on the author’s expert understanding of the gargantuan challenges that would have to be overcome to ever make quantum computing a reality. Knowledge of secondary-school-level physics and math will be sufficient for understanding most of the text.
Download or read book Quantum State Estimation written by Matteo Paris and published by Springer Science & Business Media. This book was released on 2004-08-11 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a comprehensive survey of most of the theoretical and experimental achievements in the field of quantum estimation of states and operations. Albeit still quite young, this field has already been recognized as a necessary tool for research in quantum optics and quantum information, beyond being a fascinating subject in its own right since it touches upon the conceptual foundations of quantum mechanics. The book consists of twelve extensive lectures that are essentially self-contained and modular, allowing combination of various chapters as a basis for advanced courses and seminars on theoretical or experimental aspects. The last two chapters, for instance, form a self-contained exposition on quantum discrimination problems. The book will benefit graduate students and newcomers to the field as a high-level but accessible textbook, lecturers in search for advanced course material and researchers wishing to consult a modern and authoritative source of reference.
