40 research outputs found

    Population-only decay map for n-qubit n-partite inseparability detection

    Get PDF
    We introduce a new positive linear map for a single qubit. This map is a decay only in populations of a single-qubit density operator. It is shown that an n-fold product of this map may be used for a detection of n-partite inseparability of an n-qubit density operator (i.e., detection of impossibility of representing a density operator in the form of a convex combination of products of density operators of individual qubits). This product map is also investigated in relation to a variant of the entanglement detection method mentioned by Laskowski and Zukowski.Comment: 5 pages, 1 figure, RevTex4, v2 minor grammatical changes, typos correcte

    Stripe formation in horizontally oscillating granular suspensions

    Full text link
    We present the results of an experimental study of pattern formation in horizontally oscillating granular suspensions. Starting from a homogeneous state, the suspension turns into a striped pattern within a specific range of frequencies and amplitudes of oscillation. We observe an initial development of layered structures perpendicular to the vibration direction and a gradual coarsening of the stripes. However, both processes gradually slow down and eventually saturate. The probability distribution of the stripe width approaches a nonmonotonic steady-state form which can be approximated by a Poisson distribution. We observe similar structures in MD simulations of soft spherical particles coupled to the motion of the surrounding fluid.Comment: 7 pages, 8 figures, to appear in Europhys. Lett. (2014

    Single-experiment-detectable multipartite entanglement witness for ensemble quantum computing

    Full text link
    In this paper we provide an operational method to detect multipartite entanglement in ensemble-based quantum computing. This method is based on the concept of entanglement witness. We decompose the entanglement witness for each class of multipartite entanglement into nonlocal operations in addition to local measurements. Individual single qubit measurements are performed simultaneously, hence complete detection of entanglement is performed in a single run experiment. This approach is particularly important for experiments where it is operationally difficult to prepare several copies of an unknown quantum state and in this sense the introduced scheme in this work is superior to the generally used entanglement witnesses that require a number of experiments and preparation of copies of quantum state.Comment: 9 pages, 5 figures, minor changes have been mad

    Evaluating measures of nonclassical correlation in a multipartite quantum system

    Full text link
    We introduce and compare several measures of nonclassical correlation defined on the basis of a widely-recognized paradigm claiming that a multipartite system represented by a density matrix having no product eigenbasis possesses nonclassical correlation.Comment: 6 pages, 3 figures, submitted to Proc. NIC@QS0

    A quantum genetic algorithm with quantum crossover and mutation operations

    Full text link
    In the context of evolutionary quantum computing in the literal meaning, a quantum crossover operation has not been introduced so far. Here, we introduce a novel quantum genetic algorithm which has a quantum crossover procedure performing crossovers among all chromosomes in parallel for each generation. A complexity analysis shows that a quadratic speedup is achieved over its classical counterpart in the dominant factor of the run time to handle each generation.Comment: 21 pages, 1 table, v2: typos corrected, minor modifications in sections 3.5 and 4, v3: minor revision, title changed (original title: Semiclassical genetic algorithm with quantum crossover and mutation operations), v4: minor revision, v5: minor grammatical corrections, to appear in QI

    Economical (k,m)-threshold controlled quantum teleportation

    Full text link
    We study a (k,m)-threshold controlling scheme for controlled quantum teleportation. A standard polynomial coding over GF(p) with prime p > m-1 needs to distribute a d-dimensional qudit with d >= p to each controller for this purpose. We propose a scheme using m qubits (two-dimensional qudits) for the controllers' portion, following a discussion on the benefit of a quantum control in comparison to a classical control of a quantum teleportation.Comment: 11 pages, 2 figures, v2: minor revision, discussions improved, an equation corrected in procedure (A) of section 4.3, v3: major revision, protocols extended, citations added, v4: minor grammatical revision, v5: minor revision, discussions extende

    Quantum teleportation with nonclassical correlated states in noninertial frames

    Full text link
    Quantum teleportation is studied in noninertial frame, for fermionic case, when Alice and Bob share a general nonclassical correlated state. In noninertial frames two fidelities of teleportation are given. It is found that the average fidelity of teleportation from a separable and nonclassical correlated state is increasing with the amount of nonclassical correlation of the state. However, for any particular nonclassical correlated state, the fidelity of teleportation decreases by increasing the acceleration.Comment: 10 pages, 3 figures, expanded version to appear in Quantum Inf. Proces

    Women and psychological trauma of 9/11 in Amy Waldman’s The Submission

    Get PDF
    On September 11, 2001, the world was stunned into silence as four hijacked airplanes crashed into two of America’s iconic landmarks, namely the World Trade Centre and the Pentagon. For the first time, perhaps since the Vietnam War, the entire United States of America was engulfed in a mutual sense of loss and inconsolable grief. 2996 people, a vast number of them unarmed civilians including all the passengers aboard the four hijacked airplanes, lost their lives in what was perceived by many to be the worst terrorist attack of the twenty-first century. Occurrence of such a colossal tragedy has led to producing a large corpus of textual representation of the event including countless novels such as Amy Waldman’s The Submission (2012). This study focuses on analysing The Submission by Amy Waldman using the theory of Psychoanalysis to explore the concept of psychological trauma and the effects of PTSD (Posttraumatic Stress Disorder) on female characters affected by the tragedy of 9/11. The analysis, which is mostly based on Wilson and Keane (2004) and Caruth (2001) psychoanalysis theories, seeks to explore Waldman’s perception of the process of healing from the devastating tragedy and psychological trauma of the female characters of the story. It is believed that Waldman’s novel does not only portray the trauma of the characters but also presents the path of recovery and overcoming the PTSD of those who were emotionally wounded by the tragedy of 9/11
    corecore