High-Probability Quantum State Transfer between nodes of an Open Chain of 1/2 Spins with ${XXZ}$ HamiltonianHigh-Probability Quantum State Transfer between nodes of an Open Chain of 1/2 Spins with ${XXZ}$ Hamiltonian

Edward B. Fel’dman, Alexander Ivanovich Zenchuk

This paper concerns the problem of the high probability state transfer (HPST) among different nodes of the chains of 1/2-spins with the ${XXZ}$ Hamiltonian. This effect is possible due to the suitably distributed weak bonds in the chain. We show that the arbitrary initial state may be transfered with the high probability to any node of the four-node chain with strong end bonds. Varying bonds in the six-node chain one can provide the HPSTs among two end nodes and two symmetrically placed inner nodes. We also construct the eight-node chain with the HPSTs among all of them.This paper concerns the problem of the high probability state transfer (HPST) among different nodes of the chains of 1/2-spins with the ${XXZ}$ Hamiltonian. This effect is possible due to the suitably distributed weak bonds in the chain. We show that the arbitrary initial state may be transfered with the high probability to any node of the four-node chain with strong end bonds. Varying bonds in the six-node chain one can provide the HPSTs among two end nodes and two symmetrically placed inner nodes. We also construct the eight-node chain with the HPSTs among all of them.

Sep 11, 20080 citations

Probability models

Stanley Gudder, Nino Zanghı̀

Il Nuovo cimento della Società italiana di fisica. B/Il Nuovo cimento BFeb 1, 198413 citations

Asymptotically perfect efficient quantum state transfer across uniform chains with two impurities

Xining Chen, Robert Mereau, David L. Feder

The ability to transfer quantum information from one location to another with high probability is of central importance to quantum information science. Unfortunately, for the simplest system of a uniform chain (a spin chain or a particle in a one-dimensional lattice), the state transfer time grows exponentially in the chain length $N$ at fixed transfer probability. In this work we show that the addition of an impurity near each end point, coupled to the uniform chain with strength $w$ , is sufficient to ensure efficient and high-probability state transfer. An eigenstate localized in the vicinity of the impurity can be tuned into resonance with chain-extended states by adjusting $w(N)\ensuremath{\propto}{N}^{1/2}$; the resulting avoided crossing yields resonant eigenstates with large amplitudes on the chain end points and approximately equidistant eigenvalues. The state transfer time scales as $t\ensuremath{\propto}{N}^{3/2}$, and its transfer probability $P$ approaches unity in the thermodynamic limit $N\ensuremath{\rightarrow}\ensuremath{\infty}$; the error scales as $1\ensuremath{-}P\ensuremath{\propto}{N}^{\ensuremath{-}1}$. Thus, with the addition of two impurities, asymptotically perfect efficient state transfer with a uniform chain is possible even in the absence of external control.The ability to transfer quantum information from one location to another with high probability is of central importance to quantum information science. Unfortunately, for the simplest system of a uniform chain (a spin chain or a particle in a one-dimensional lattice), the state transfer time grows exponentially in the chain length $N$ at fixed transfer probability. In this work we show that the addition of an impurity near each end point, coupled to the uniform chain with strength $w$, is sufficient to ensure efficient and high-probability state transfer. An eigenstate localized in the vicinity of the impurity can be tuned into resonance with chain-extended states by adjusting $w(N)\ensuremath{\propto}{N}^{1/2}$; the resulting avoided crossing yields resonant eigenstates with large amplitudes on the chain end points and approximately equidistant eigenvalues. The state transfer time scales as $t\ensuremath{\propto}{N}^{3/2}$, and its transfer probability $P$ approaches unity in the thermodynamic limit $N\ensuremath{\rightarrow}\ensuremath{\infty}$; the error scales as $1\ensuremath{-}P\ensuremath{\propto}{N}^{\ensuremath{-}1}$. Thus, with the addition of two impurities, asymptotically perfect efficient state transfer with a uniform chain is possible even in the absence of external control.

arXiv:1511.00038Physical Review AJan 27, 201623 citations

Probability Postulate

Brian P. Anderson

SPIE eBooksSep 12, 20190 citations

Probability as typicality

Sérgio B. Volchan

arXiv:physics/0611172Studies in History and Philosophy of Science Part B Studies in History and Philosophy of Modern PhysicsMar 3, 200723 citations

Extensions and composites in topos quantum theory

Jisho Miyazaki

Topos quantum theory provides representations of quantum states as direct generalizations of the probability distribution, namely probability valuation. In this article, we consider extensions of a known bijective correspondence between quantum states and probability valuations to composite systems and to state transformations. We show that multipartite probability valuations on composite systems have a bijective correspondence to positive over pure tensor states, according to a candidate definition of the composite systems in topos quantum theory. Among the multipartite probability valuations, a special attention is placed to Markov chains which are defined by generalizing classical Markov chains from probability theory. We find an incompatibility between the multipartite probability valuations and a monogamy property of quantum states, which trivializes the Markov chains to product probability valuations. Several observations on the transformations of probability valuations are deduced from the results on multipartite probability valuations, through duality relations between multipartite states and state transformations.Topos quantum theory provides representations of quantum states as direct generalizations of the probability distribution, namely probability valuation. In this article, we consider extensions of a known bijective correspondence between quantum states and probability valuations to composite systems and to state transformations. We show that multipartite probability valuations on composite systems have a bijective correspondence to positive over pure tensor states, according to a candidate definition of the composite systems in topos quantum theory. Among the multipartite probability valuations, a special attention is placed to Markov chains which are defined by generalizing classical Markov chains from probability theory. We find an incompatibility between the multipartite probability valuations and a monogamy property of quantum states, which trivializes the Markov chains to product probability valuations. Several observations on the transformations of probability valuations are deduced from the results on multipartite probability valuations, through duality relations between multipartite states and state transformations.

May 23, 20160 citations

High-Probability Quantum State Transfer between nodes of an Open Chain of 1/2 Spins with

{XXZ}

Hamiltonian

This paper concerns the problem of the high probability state transfer (HPST) among different nodes of the chains of 1/2-spins with the

{XXZ}

Hamiltonian. This effect is possible due to the suitably distributed weak bonds in the chain. We show that the arbitrary initial state may be transfered with the high probability to any node of the four-node chain with strong end bonds. Varying bonds in the six-node chain one can provide the HPSTs among two end nodes and two symmetrically placed inner nodes. We also construct the eight-node chain with the HPSTs among all of them.

N

at fixed transfer probability. In this work we show that the addition of an impurity near each end point, coupled to the uniform chain with strength

w

, is sufficient to ensure efficient and high-probability state transfer. An eigenstate localized in the vicinity of the impurity can be tuned into resonance with chain-extended states by adjusting $w(N)\ensuremath{\propto}{N}^{1/2}$; the resulting avoided crossing yields resonant eigenstates with large amplitudes on the chain end points and approximately equidistant eigenvalues. The state transfer time scales as $t\ensuremath{\propto}{N}^{3/2}$, and its transfer probability

P

approaches unity in the thermodynamic limit $N\ensuremath{\rightarrow}\ensuremath{\infty}$; the error scales as $1\ensuremath{-}P\ensuremath{\propto}{N}^{\ensuremath{-}1}$. Thus, with the addition of two impurities, asymptotically perfect efficient state transfer with a uniform chain is possible even in the absence of external control.