BEC and optical lattices
... Centre for Quantum Physics & Technology, Clarendon Laboratory, University of Oxford. ...
... Centre for Quantum Physics & Technology, Clarendon Laboratory, University of Oxford. ...
Qubit metrology for building a fault-tolerant quantum
... can vary in amplitude, duration and frequency. More fundamentally, the Heisenberg uncertainty principle states that it is impossible to directly stabilise a single qubit as any measurement of a bit-flip error will produce a random flip in phase. The key to quantum error correction is measuring qubit p ...
... can vary in amplitude, duration and frequency. More fundamentally, the Heisenberg uncertainty principle states that it is impossible to directly stabilise a single qubit as any measurement of a bit-flip error will produce a random flip in phase. The key to quantum error correction is measuring qubit p ...
The effect of quantum confinement and discrete dopants in
... simulation is therefore required to obtain results in quantitative agreement with experiments. As geometries are scaled down, the effect of the discrete distribution of dopants also becomes significant and affects important properties such as the threshold voltage. Our code has allowed us to take in ...
... simulation is therefore required to obtain results in quantitative agreement with experiments. As geometries are scaled down, the effect of the discrete distribution of dopants also becomes significant and affects important properties such as the threshold voltage. Our code has allowed us to take in ...
Decay rates of planar helium - the Max Planck Institute for the
... the dynamics of fragmentation is planar, even for non-zero angular momentum. In the presence, e.g., of an external electromagnetic field, angular momentum is however not conserved. Notwithstanding, even if an external perturbation mixes the angular degrees of freedom of the two-electron dynamics, th ...
... the dynamics of fragmentation is planar, even for non-zero angular momentum. In the presence, e.g., of an external electromagnetic field, angular momentum is however not conserved. Notwithstanding, even if an external perturbation mixes the angular degrees of freedom of the two-electron dynamics, th ...
Measurement-based and Universal Blind Quantum Computation
... Having obtained the rigourous mathematical model underlying MBQC, we then present how this model suggests new techniques for designing quantum protocols. We present a protocol, called Universal Blind Quantum Computation (UBQC) which allows a client to have a server carry out a quantum computation fo ...
... Having obtained the rigourous mathematical model underlying MBQC, we then present how this model suggests new techniques for designing quantum protocols. We present a protocol, called Universal Blind Quantum Computation (UBQC) which allows a client to have a server carry out a quantum computation fo ...
Bell-Inequality Violations with Single Photons Entangled in Momentum and Polarization
... that all is said and done. Hidden-variable theories that are realistic but non-local could still negate quantum mechanics. A recent experimental test has started the task of addressing this question (Groblacher et al 2007), but the jury is out about how conclusively (Aspect 2007). There are also oth ...
... that all is said and done. Hidden-variable theories that are realistic but non-local could still negate quantum mechanics. A recent experimental test has started the task of addressing this question (Groblacher et al 2007), but the jury is out about how conclusively (Aspect 2007). There are also oth ...
Quantum Interaction Approach in Cognition, Artificial Intelligence
... experiments [43], [44] which measured the deviation from classical set-theoretic membership weights of exemplars with respect to pairs of concepts and their conjunction or disjunction. Hampton’s investigation was motivated by the so-called Guppy effect in concept conjunction found by Osherson and Sm ...
... experiments [43], [44] which measured the deviation from classical set-theoretic membership weights of exemplars with respect to pairs of concepts and their conjunction or disjunction. Hampton’s investigation was motivated by the so-called Guppy effect in concept conjunction found by Osherson and Sm ...
Entangled Quartet
... field. Atomic ensembles such as those used by the authors have already reached lightstorage times of milliseconds at the singlephoton level7,8. If those storage times can be extended to seconds, and some other technical per formance parameters improved, such sources will have a variety of potenti ...
... field. Atomic ensembles such as those used by the authors have already reached lightstorage times of milliseconds at the singlephoton level7,8. If those storage times can be extended to seconds, and some other technical per formance parameters improved, such sources will have a variety of potenti ...
computing
... 23 = 8 different configurations that can represent, for example, the integers from 0 to 7. However, a register composed of three classical bits can store only one number at a given moment of time. Enter qubits and quantum registers: A qubit is a quantum system in which the Boolean states 0 and 1 are ...
... 23 = 8 different configurations that can represent, for example, the integers from 0 to 7. However, a register composed of three classical bits can store only one number at a given moment of time. Enter qubits and quantum registers: A qubit is a quantum system in which the Boolean states 0 and 1 are ...
Operator Imprecision and Scaling of Shor’s Algorithm
... performance of the algorithm in such a way that the polynomial complexity of the algorithm no longer describes the scaling behavior of the algorithm’s execution time. It is possible to show that, in the presence of operator precision errors, Shor’s algorithm is no more efficient than classical algo ...
... performance of the algorithm in such a way that the polynomial complexity of the algorithm no longer describes the scaling behavior of the algorithm’s execution time. It is possible to show that, in the presence of operator precision errors, Shor’s algorithm is no more efficient than classical algo ...
Particles in a Quantum Ontology of Properties
... The essential role of individual constants and variables is not limited to traditional logic: the vast majority of systems of logic, even extensions of traditional logic and deviant systems (see Haack 1974, 1978), use them; an ontology populated by individual objects is thus universally presupposed. ...
... The essential role of individual constants and variables is not limited to traditional logic: the vast majority of systems of logic, even extensions of traditional logic and deviant systems (see Haack 1974, 1978), use them; an ontology populated by individual objects is thus universally presupposed. ...
PDF only - at www.arxiv.org.
... feature of chemistry, biology, and human life. It does not take seriously the physics and biology of the real world but rather represents an idealised view of things which is reasonably accurate in certain very restricted situations (for example laboratory experiments where all external influences e ...
... feature of chemistry, biology, and human life. It does not take seriously the physics and biology of the real world but rather represents an idealised view of things which is reasonably accurate in certain very restricted situations (for example laboratory experiments where all external influences e ...
26_IJFPS_March_2012_..
... diagnosis in diseases. Detective Quantum Efficiency the ratio of noise equivalent quanta to the actual number of exposure quanta from which the image was made (Martin, Sharp, & Sutton, 1999), which can also be viewed as the fraction of photons that are detected “correctly” (Prince & Links, 2006). Sc ...
... diagnosis in diseases. Detective Quantum Efficiency the ratio of noise equivalent quanta to the actual number of exposure quanta from which the image was made (Martin, Sharp, & Sutton, 1999), which can also be viewed as the fraction of photons that are detected “correctly” (Prince & Links, 2006). Sc ...
Quantum key distribution
Quantum key distribution (QKD) uses quantum mechanics to guarantee secure communication. It enables two parties to produce a shared random secret key known only to them, which can then be used to encrypt and decrypt messages. It is often incorrectly called quantum cryptography, as it is the most well known example of the group of quantum cryptographic tasks.An important and unique property of quantum key distribution is the ability of the two communicating users to detect the presence of any third party trying to gain knowledge of the key. This results from a fundamental aspect of quantum mechanics: the process of measuring a quantum system in general disturbs the system. A third party trying to eavesdrop on the key must in some way measure it, thus introducing detectable anomalies. By using quantum superpositions or quantum entanglement and transmitting information in quantum states, a communication system can be implemented which detects eavesdropping. If the level of eavesdropping is below a certain threshold, a key can be produced that is guaranteed to be secure (i.e. the eavesdropper has no information about it), otherwise no secure key is possible and communication is aborted.The security of encryption that uses quantum key distribution relies on the foundations of quantum mechanics, in contrast to traditional public key cryptography which relies on the computational difficulty of certain mathematical functions, and cannot provide any indication of eavesdropping at any point in the communication process, or any mathematical proof as to the actual complexity of reversing the one-way functions used. QKD has provable security based on information theory, and forward secrecy.Quantum key distribution is only used to produce and distribute a key, not to transmit any message data. This key can then be used with any chosen encryption algorithm to encrypt (and decrypt) a message, which can then be transmitted over a standard communication channel. The algorithm most commonly associated with QKD is the one-time pad, as it is provably secure when used with a secret, random key. In real world situations, it is often also used with encryption using symmetric key algorithms like the Advanced Encryption Standard algorithm. In the case of QKD this comparison is based on the assumption of perfect single-photon sources and detectors, that cannot be easily implemented.