Results 1  10
of
68
Topics in quantum computers
, 1996
"... Abstract. I provide an introduction to quantum computers, describing how they might be realized using language accessible to a solid state physicist. A listing of the minimal requirements for creating a quantum computer is given. I also discuss several recent developments in the area of quantum erro ..."
Abstract

Cited by 67 (1 self)
 Add to MetaCart
Abstract. I provide an introduction to quantum computers, describing how they might be realized using language accessible to a solid state physicist. A listing of the minimal requirements for creating a quantum computer is given. I also discuss several recent developments in the area of quantum error correction, a subject of importance not only to quantum computation, but also to some aspects of the foundations of quantum theory. 1. What is a quantum computer? I don’t think that I will spend many words here saying why there has been a considerable growth of interest in the last couple of years in the subject of quantum computation. There has been a spate of reviews[1, 2, 3], semipopular articles[4], and press accounts[5] giving, on the whole, a very good overview of the subject. At some level, the recent interest simply arises from the very traditional movement of computation into ever more miniature worlds, and what could be more miniature than the world of the single quantum? At another level, though, interest has arisen because the rules of
Efficient simulation of quantum systems by quantum computers. Online preprint quantph/9603026
, 1996
"... We show that the time evolution of the wave function of a quantummechanical manyparticle system can be simulated precisely and efficiently on a quantum computer. The time needed for such a simulation is comparable to the time of a conventional simulation of the corresponding classical system, a per ..."
Abstract

Cited by 58 (0 self)
 Add to MetaCart
We show that the time evolution of the wave function of a quantummechanical manyparticle system can be simulated precisely and efficiently on a quantum computer. The time needed for such a simulation is comparable to the time of a conventional simulation of the corresponding classical system, a performance which can’t be expected from any classical simulation of a quantum system. We then show how quantities of interest, like the energy spectrum of a system, can be obtained. We also indicate that ultimately the simulation of quantum field theory might be possible on large quantum computers.
Simulating quantum mechanics on a quantum computer
 PHYSICA D
, 1998
"... Algorithms are described for efficiently simulating quantum mechanical systems on quantum computers. A class of algorithms for simulating the Schrödinger equation for interacting manybody systems are presented in some detail. These algorithms would make it possible to simulate nonrelativistic quant ..."
Abstract

Cited by 42 (3 self)
 Add to MetaCart
Algorithms are described for efficiently simulating quantum mechanical systems on quantum computers. A class of algorithms for simulating the Schrödinger equation for interacting manybody systems are presented in some detail. These algorithms would make it possible to simulate nonrelativistic quantum systems on a quantum computer with an exponential speedup compared to simulations on classical computers. Issues involved in simulating relativistic systems of Dirac or gauge particles are discussed.
Quantum factoring, discrete logarithms and the hidden subgroup problem
"... Amongst the most remarkable successes of quantum computation are Shor’s efficient quantum algorithms for the computational tasks of integer factorisation and the evaluation of discrete logarithms. In this article we review the essential ingredients of these algorithms and draw out the unifying gener ..."
Abstract

Cited by 24 (0 self)
 Add to MetaCart
Amongst the most remarkable successes of quantum computation are Shor’s efficient quantum algorithms for the computational tasks of integer factorisation and the evaluation of discrete logarithms. In this article we review the essential ingredients of these algorithms and draw out the unifying generalization of the socalled abelian hidden subgroup problem. This involves an unexpectedly harmonious alignment of the formalism of quantum physics with the elegant mathematical theory of group representations and fourier transforms on finite groups. Finally we consider the nonabelian hidden subgroup problem mentioning some open questions where future quantum algorithms may be expected to have a substantial impact. 1
Information and Computation: Classical and Quantum Aspects
 REVIEWS OF MODERN PHYSICS
, 2001
"... Quantum theory has found a new field of applications in the realm of information and computation during the recent years. This paper reviews how quantum physics allows information coding in classically unexpected and subtle nonlocal ways, as well as information processing with an efficiency largely ..."
Abstract

Cited by 23 (2 self)
 Add to MetaCart
Quantum theory has found a new field of applications in the realm of information and computation during the recent years. This paper reviews how quantum physics allows information coding in classically unexpected and subtle nonlocal ways, as well as information processing with an efficiency largely surpassing that of the present and foreseeable classical computers. Some outstanding aspects of classical and quantum information theory will be addressed here. Quantum teleportation, dense coding, and quantum cryptography are discussed as a few samples of the impact of quanta in the transmission of information. Quantum logic gates and quantum algorithms are also discussed as instances of the improvement in information processing by a quantum computer. We provide finally some examples of current experimental
A Rosetta stone for quantum mechanics with an introduction to quantum computation
, 2002
"... Abstract. The purpose of these lecture notes is to provide readers, who have some mathematical background but little or no exposure to quantum mechanics and quantum computation, with enough material to begin reading ..."
Abstract

Cited by 21 (11 self)
 Add to MetaCart
Abstract. The purpose of these lecture notes is to provide readers, who have some mathematical background but little or no exposure to quantum mechanics and quantum computation, with enough material to begin reading
The initialization problem in quantum computing
 LANL Archive quantph/9805002
, 1999
"... The problem of initializing phase in a quantum computing system is considered. The initialization of phases is a problem when the system is initially present in a superposition state as well as in the application of the quantum gate transformations, since each gate will introduce phase uncertainty. ..."
Abstract

Cited by 20 (7 self)
 Add to MetaCart
The problem of initializing phase in a quantum computing system is considered. The initialization of phases is a problem when the system is initially present in a superposition state as well as in the application of the quantum gate transformations, since each gate will introduce phase uncertainty. The accumulation of these random phases will reduce the effectiveness of the recently proposed quantum computing schemes. The paper also presents general observations on the nonlocal nature of quantum errors and the expected performance of the proposed quantum errorcorrection codes that are based on the assumption that the errors are either bitflip or phaseflip or both. It is argued that these codes cannot directly solve the initialization problem of quantum computing.
A Quantum Logic Array Microarchitecture: Scalable Quantum Data Movement and Computation
 Proceedings of the 38th International Symposium on Microarchitecture MICRO38
, 2005
"... Recent experimental advances have demonstrated technologies capable of supporting scalable quantum computation. A critical next step is how to put those technologies together into a scalable, faulttolerant system that is also feasible. We propose a Quantum Logic Array (QLA) microarchitecture that f ..."
Abstract

Cited by 19 (1 self)
 Add to MetaCart
Recent experimental advances have demonstrated technologies capable of supporting scalable quantum computation. A critical next step is how to put those technologies together into a scalable, faulttolerant system that is also feasible. We propose a Quantum Logic Array (QLA) microarchitecture that forms the foundation of such a system. The QLA focuses on the communication resources necessary to efficiently support faulttolerant computations. We leverage the extensive groundwork in quantum error correction theory and provide analysis that shows that our system is both asymptotically and empirically fault tolerant. Specifically, we use the QLA to implement a hierarchical, arraybased design and a logarithmic expense quantumteleportation communication protocol. Our goal is to overcome the primary scalability challenges of reliability, communication, and quantum resource distribution that plague current proposals for largescale quantum computing. Our work complements recent work by Balenseifer et al [1], which studies the software tool chain necessary to simplify development of quantum applications; here we focus on modeling a fullscale optimized microarchitecture for scalable computing. 1.
Decoherence, Einselection and the Existential Interpretation (The Rough Guide)
 PHIL. TRANS. R. SOC. LOND. A
, 1998
"... The roles of decoherence and environmentinduced superselection in the emergence of the classical from the quantum substrate are described. The stability of correlations between the einselected quantum pointer states and the environment allows them to exist almost as objectively as classical states ..."
Abstract

Cited by 19 (0 self)
 Add to MetaCart
The roles of decoherence and environmentinduced superselection in the emergence of the classical from the quantum substrate are described. The stability of correlations between the einselected quantum pointer states and the environment allows them to exist almost as objectively as classical states were once thought to exist: there are ways of finding out what is the pointer state of the system which uses redundancy of its correlations with the environment, and which leave einselected states essentially unperturbed. This relatively objective existence of certain quantum states facilitates operational definition of probabilities in the quantum setting. Moreover, once there are states that ‘exist ’ and can be ‘found out’, a ‘collapse ’ in the traditional sense is no longer necessary—in effect, it has already happened. The role of the preferred states in the processing and storage of information is emphasized. The existential interpretation based on the relatively objective existence of stable correlations between the einselected states of observers’ memory and in the outside universe is formulated and discussed.