Quantum Information Processing (QUANTUM INF PROCESS)

Publications in this journal

• Source

  Available from: ArXiv

  Article: On the Efficiency of Quantum Algorithms for Hamiltonian Simulation

  Anargyros Papageorgiou, Chi Zhang
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  ABSTRACT: We study the efficiency of algorithms simulating a system evolving with Hamiltonian $H=\sum_{j=1}^m H_j$. We consider high order splitting methods that play a key role in quantum Hamiltonian simulation. We obtain upper bounds on the number of exponentials required to approximate $e^{-iHt}$ with error $\e$. Moreover, we derive the order of the splitting method that optimizes the cost of the resulting algorithm. We show significant speedups relative to previously known results. Comment: 15 pages
  Quantum Information Processing 05/2012; 11(2):541-581.
• Article: Faithful teleportation via multi-particle quantum states in a network with many agents

  Min Jiang, Hui Li, Zeng-ke Zhang, Jia Zeng
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  ABSTRACT: An efficient scheme is proposed for faithful teleportation of an arbitrary unknown multi-particle state via multi-particle quantum states, in which the teleportation is completely deterministic providing that one can successfully construct a group of EPR pairs. Our scheme can effectively avoid possible destruction of the unknown state to be teleported, which however may occur in existing probabilistic teleportation schemes. In addition, we develop a scheme for establishing a faithful quantum channel for both indirect and direct teleportation multi-particle system, which can be applied in a teleportation network where intermediate agents exist between a sender and a receiver. Compared to the indirect construction of the faithful channel, the required auxiliary particle resources, local operations and classical communications in the direct construction scheme are considerably reduced. KeywordsProbabilistic teleportation–Multi-particle state–Multi agents–Auxiliary particle–Bell-state measurement
  Quantum Information Processing 05/2012; 11(1):23-40.
• Article: On probability polynomials of 1D quantum walk

  Mark W. Coffey, Matthew S. Heller
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  ABSTRACT: We investigate a set of polynomials arising from one dimensional quantum walk with a single-parameter coin operator. In the process, explicit hypergeometric function expressions for these polynomials are presented. An explicit expression is also given for a limit probability for the special case of Hadamard walk. KeywordsQuantum walk–Coin operator–Shift operator–Variance–Probability polynomial–Gauss hypergeometric function
  Quantum Information Processing 05/2012; 10(2):271-277.
• Article: Asymmetric quantum Reed-Solomon and generalized Reed-Solomon codes

  Giuliano G. La Guardia
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  ABSTRACT: Two new families of asymmetric quantum codes are constructed in this paper. The first one is derived from the Calderbank-Shor-Steane (CSS) construction applied to classical Reed-Solomon (RS) codes, providing quantum codes with parameters [[N =l(q l −1), K =l(q l −2d+c+1), d z ≥ d/d x ≥ (d−c)]] q , where q is a prime power and d > c+1, c ≥ 1, l ≥ 1 are integers. The second family is derived from the CSS construction applied to classical generalized RS codes, generating quantum codes with parameters [[N = mn, K=m(2k−n+c), d z ≥ d/d x ≥ (d−c)]] q , where q is a prime power, 1< k < n < 2k+c ≤ q m , k=n − d+1, and n, d > c+1, c ≥ 1, m≥ 1 are integers. Although the second proposed construction generalizes the first one, the techniques developed in both constructions are slightly different. These new codes have parameters better than or comparable to the ones available in the literature. Additionally, the proposed codes can be utilized in quantum channels having great asymmetry, that is, quantum channels in which the probability of occurrence of phase-shift errors is large when compared to the probability of occurrence of qudit-flip errors. KeywordsQuantum codes–Generalized Reed-Solomon codes–Finite fields
  Quantum Information Processing 05/2012; 11(2):591-604.
• Article: Gregg Jaeger: Entanglement, Information, and the Interpretation of Quantum Mechanics (The Frontiers Collection)

  Giacomo Mauro D’Ariano
  Quantum Information Processing 05/2012; 11(1):311-312.
• Article: New quantum private comparison protocol using EPR pairs

  Hsin-Yi Tseng, Jason Lin, Tzonelih Hwang
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  ABSTRACT: Based on EPR pairs, this paper proposes a different quantum private comparison (QPC) protocol enabling two parties to compare the equality of their information without revealing the information content. Due to the use of quantum entanglement of Bell state as well as one-way quantum transmission, the new protocol provides easier implementation as well as better qubit efficiency (near 50%) than the other QPCs. It is secure against Trojan horse attack and other well-known attacks. KeywordsEPR pair–Quantum private comparison–Bell state–Qubit efficiency
  Quantum Information Processing 05/2012; 11(2):373-384.
• Article: Entanglement and purity loss for the system of two 2-level atoms in the presence of the Stark shift

  Hosny A. Hessian, M. Hashem
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  ABSTRACT: In this paper, we have presented an analytic solution for two 2-level identical atoms interacting with a single-mode quantized radiation field, taking into account the level shifts produced by Stark shift. We assume that the two atoms are initially prepared in the exited state and the field in a coherent state. We investigate the purity loss of the system and bipartite partitions of the system. The effects of the Stark shift on the purity loss of the system and different bipartite partitions of the system (field-two atoms, atom-(field+atom)) through the tangles are considered. In particular, the effect of the Stark shift on the amount of entanglement between atoms and field is evaluated by the negativity.
  Quantum Information Processing 05/2012; 10(4):543-556.
• Article: Catalysis of entanglement transformation for 2 × 2-dimensional mixed states

  De-chao Li, Zhong-ke Shi
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  ABSTRACT: At first, the ability of pure states as an entanglement catalysts for transformation between 2× 2-dimensional mixed states is discussed. Necessary and sufficient conditions for the transformation between 2× 2-dimensional rank 2 mixed states by entanglement-assisted LOCC operations (ELOCC) are then presented. In addition, the method to construct an entanglement catalyst for transformation between 2× 2-dimensional rank 2 mixed states is illustrated by an example. KeywordsTransformation–Entanglement catalysis–Mixed state
  Quantum Information Processing 05/2012; 10(5):697-704.
• Article: Quantum key distribution via tripartite coherent states

  A. El Allati, M. El Baz, Y. Hassouni
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  ABSTRACT: We propose a quantum key distribution protocol using Greenberger Horne Zeilinger tripartite coherent states. The sender and the receiver share similar key by exchanging the correlation coherent states, without basis reconciliation. This allows the protocol to have a transmission efficiency of 100% in a perfect quantum channel. The security of the protocol is ensured by tripartite coherent states correlation and homodyne detection, which allows to detect any eavesdropping easily. KeywordsQuantum key distribution–Coherent states–Greenberger-Horne-Zeilinger state–Entanglement–Homodyne detection
  Quantum Information Processing 05/2012; 10(5):589-602.
• Article: Investigating the implementation of restricted sets of multiqubit operations on distant qubits: a communication complexity perspective

  Haozhen Situ, Daowen Qiu
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  ABSTRACT: We propose a protocol for Alice to implement a multiqubit quantum operation from the restricted sets on distant qubits possessed by Bob, and then we investigate the communication complexity of the task in different communication scenarios. By comparing with the previous work, our protocol works without prior sharing of entanglement, and requires less communication resources than the previous protocol in the qubit-transmission scenario. Furthermore, we generalize our protocol to d-dimensional operations. KeywordsQuantum communication–Nonlocal operations–Remote implementation–Communication complexity
  Quantum Information Processing 05/2012; 10(5):609-618.
• Article: Tripartite entanglement sudden death in Yang-Baxter systems

  Taotao Hu, Hang Ren, Kang Xue
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  ABSTRACT: In this paper, we derive unitary Yang-Baxter \breveR(q, j){\breve{R}(\theta, \varphi)} matrices from the 88\mathbbM{8\times8\,\mathbb{M}} matrix and the 4×4M matrix by Yang-Baxteration approach, where \mathbbM/M{\mathbb{M}/M} is the image of the braid group representation. In Yang-Baxter systems, we explore the evolution of tripartite negativity for three qubits Greenberger-Horne-Zeilinger (GHZ)-type states and W-type states and investigate the evolution of the bipartite concurrence for 2 qubits Bell-type states. We show that tripartite entanglement sudden death (ESD) and bipartite ESD all can happen in Yang-Baxter systems and find that ESD all are sensitive to the initial condition. Interestingly, we find that in the Yang-Baxter system, GHZ-type states can have bipartite entanglement and bipartite ESD, and find that in some initial conditions, W-type states have tripartite ESD while they have no bipartite Entanglement. It is worth noting that the meaningful parameter j{\varphi} has great influence on bipartite ESD for two qubits Bell-type states in the Yang-Baxter system. KeywordsTripartite entanglement–Entanglement sudden death–Quantum Yang-Baxter equation
  Quantum Information Processing 04/2012; 10(5):705-715.
• Article: Quantum information splitting of an arbitrary three-qubit state by using a genuinely entangled five-qubit state and a Bell-state

  Yi-you Nie, Yuan-hua Li, Jun-chang Liu, Ming-huang Sang
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  ABSTRACT: A new application of the genuinely entangled five-qubit state introduced by Brown etal. (J Phys A 38(5), 1119–1131, 2005) is investigated for quantum information splitting (QIS) of an arbitrary three-qubit state. We demonstrate that such a genuine five-qubit entangled state and a Bell-state can be used to realize the deterministic QIS of an arbitrary three-qubit state by performing the Bell-state measurements and single qubit measurement. The presented protocol is showed to be secure against certain eavesdropping attacks. KeywordsQuantum information–Quantum information splitting–Arbitrary three-qubit state–Genuinely entangled five-qubit state–Bell-state measurement
  Quantum Information Processing 04/2012; 11(2):563-569.
• Source

  Available from: ArXiv

  Article: Multipartite entangled magnon states as quantum communication channels

  E. Sriram Prasath, Sreraman Muralidharan, Chiranjib Mitra, Prasanta K. Panigrahi
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  ABSTRACT: We investigate the entanglement properties of the two magnon states and explicate conditions under which, the two magnon state becomes useful for several quantum communication protocols. We systematically study the temporal behaviour of concurrence to find out the effect of exchange interaction on entanglement. The two magnon state, which is potentially realizable in quantum dots using Heisenberg exchange interaction, is found to be suitable for carrying out deterministic teleportation of an arbitrary two qubit composite system. Further, conditions for which the channel capacity reaches “Holevo bound”, allowing four classical bits to be transmitted through two qubits are derived. Later, an unconventional protocol is given to demonstrate that this state can be used for sharing of a two qubit entangled state among two parties. KeywordsMagnon state–Entanglement–Teleportation–Superdensecoding–State sharing
  Quantum Information Processing 04/2012; 11(2):397-410.
• Article: An analytic approach to the problem of separability of quantum states based upon the theory of cones

  D. Salgado, J. L. Sánchez-Gómez, M. Ferrero
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  ABSTRACT: Exploiting the cone structure of the set of unnormalized mixed quantum states, we offer an approach to detect separability independently of the dimensions of the subsystems. We show that any mixed quantum state can be decomposed as ρ=(1−λ)C ρ +λE ρ , where C ρ is a separable matrix whose rank equals that of ρ and the rank of E ρ is strictly lower than that of ρ. With the simple choice Cr=M1ÄM2{C_{\rho}=M_{1}\otimes M_{2}} we have a necessary condition of separability in terms of λ, which is also sufficient if the rank of E ρ equals 1. We give a first extension of this result to detect genuine entanglement in multipartite states and show a natural connection between the multipartite separability problem and the classification of pure states under stochastic local operations and classical communication. We argue that this approach is not exhausted with the first simple choices included herein. KeywordsEntanglement–Separability–Cone–Bipartite–Multipartite
  Quantum Information Processing 04/2012; 10(5):633-651.
• Article: Quantifying entanglement of two relativistic particles using optimal entanglement witness

  M. A. Jafarizadeh, M. Mahdian
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  ABSTRACT: In a recent paper, it was shown that the projections of a relativistic spin operator (RSO) massive spin- \frac12{\frac{1}{2}} particle on a world-vector which can be in timelike or null tetrad direction are proportional to the helicity or Bargman-Wigner (BW) qubit, respectively. Here we consider Lorentz transformations of two-particle states, which have been constructed both in helicity basis. For convenience, instead of using the superposition of momenta we use only two momentum eigenstates (p 1 and p 2) for each particle. Consequently, in 2D momentum subspace we describe the structure of one particle in terms of the four-qubit system. We present a new approach to quantification of relativistic entanglement based on entanglement witness (EW), which is obtained by a new method of convex optimization. In addition, Lorentz invariance of entanglement using BW qubit is also studied. KeywordsRelativistic entanglement–Entanglement witnesses–Convex optimization–Two-spinor
  Quantum Information Processing 04/2012; 10(4):501-518.