Quantum repeater protocol for deterministic distribution of macroscopic entanglement

• URL: http://arxiv.org/abs/2408.00141v1
• Date: Wed, 31 Jul 2024 20:01:13 GMT
• Title: Quantum repeater protocol for deterministic distribution of macroscopic entanglement
• Authors: Alexey N. Pyrkov, Ilia D. Lazarev, Tim Byrnes,
• Abstract summary: We present a method to distribute a macroscopic amount of entanglement across long-distances using a number of operations that scales only linearly with the chain length. We show that there are particular magic'' interaction times that allow for distribution of entanglement with perfect fidelity, with no degradation with chain length.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Distributing long-distance entanglement is a fundamental goal that is necessary for a variety of tasks such as quantum communication, distributed quantum computing, and quantum metrology. Currently quantum repeater schemes typically aim to distribute one ebit at a time, the equivalent of one Bell pair's worth of entanglement. Here we present a method to distribute a macroscopic amount of entanglement across long-distances using a number of operations that scales only linearly with the chain length. The scheme involves ensembles of qubits and entangling them with an $S^z S^z$ interaction, which can be realized using atomic gas ensembles coupled by a shared optical mode. Using only local measurements on the intermediate ensembles, this leaves the ensembles at the ends of the chain entangled. We show that there are particular ``magic'' interaction times that allow for distribution of entanglement with perfect fidelity, with no degradation with chain length. The scheme is deterministic, such that with suitable local conditional unitary corrections, the same entangled state can always be prepared with good approximation.

Related papers

• Efficient Eigenstate Preparation in an Integrable Model with Hilbert Space Fragmentation [42.408991654684876]
  We consider the preparation of all the eigenstates of spin chains using quantum circuits. We showivities of the growth is also achievable for interacting models where the interaction between the particles is sufficiently simple.
  arXiv  Detail & Related papers  (2024-11-22T18:57:08Z)
• On noise in swap ASAP repeater chains: exact analytics, distributions and tight approximations [9.32782060570252]
  Losses are one of the main bottlenecks for the distribution of entanglement in quantum networks. We analytically investigate the case of equally-spaced repeaters. We find exact analytic formulae for all moments of the fidelity up to 25 segments.
  arXiv  Detail & Related papers  (2024-04-10T16:24:51Z)
• Normal quantum channels and Markovian correlated two-qubit quantum errors [77.34726150561087]
  We study general normally'' distributed random unitary transformations. On the one hand, a normal distribution induces a unital quantum channel. On the other hand, the diffusive random walk defines a unital quantum process.
  arXiv  Detail & Related papers  (2023-07-25T15:33:28Z)
• Resolving nonclassical magnon composition of a magnetic ground state via a qubit [44.99833362998488]
  We show that a direct dispersive coupling between a qubit and a noneigenmode magnon enables detecting the magnonic number states' quantum superposition. This unique coupling is found to enable control over the equilibrium magnon squeezing and a deterministic generation of squeezed even Fock states.
  arXiv  Detail & Related papers  (2023-06-08T09:30:04Z)
• Decoupling by local random unitaries without simultaneous smoothing, and applications to multi-user quantum information tasks [0.0]
  We show that a simple telescoping sum trick, together with the triangle inequality and a tensorisation property of expected-contractive coefficients of random channels, allow us to achieve general simultaneous decoupling for multiple users via local actions. We obtain bounds on the expected deviation from ideal decoupling either in the one-shot setting in terms of smooth min-entropies, or the finite block length setting in terms of R'enyi entropies. This leads to one-shot, finite block length, and simultaneous achievability results for several tasks in quantum Shannon theory.
  arXiv  Detail & Related papers  (2023-04-24T14:17:32Z)
• Exact rate analysis for quantum repeaters with imperfect memories and entanglement swapping as soon as possible [0.0]
  We present an exact rate analysis for a secret key that can be shared among two parties employing a linear quantum repeater chain. We consider additional tools and parameters such as memory cut-offs, multiplexing, initial state and swapping gate fidelities.
  arXiv  Detail & Related papers  (2022-03-19T12:55:56Z)
• Interactive Protocols for Classically-Verifiable Quantum Advantage [46.093185827838035]
  "Interactions" between a prover and a verifier can bridge the gap between verifiability and implementation. We demonstrate the first implementation of an interactive quantum advantage protocol, using an ion trap quantum computer.
  arXiv  Detail & Related papers  (2021-12-09T19:00:00Z)
• Entanglement Swapping for Repeater Chains with Finite Memory Sizes [19.436762526586204]
  We develop entanglement swapping protocols and memory allocation methods for quantum repeater chains. We determine the trade-off between the entanglement distribution rate and the memory size for temporal multiplexing techniques.
  arXiv  Detail & Related papers  (2021-11-22T05:20:10Z)
• Pretty good quantum state transfer on isotropic and anisotropic Heisenberg spin chains with tailored site dependent exchange couplings [68.8204255655161]
  We consider chains with isotropic and anisotropic Heisenberg Hamiltonian with up to 100 spins. We consider short transferred times, in particular shorter than those achievable with known time-dependent control schemes.
  arXiv  Detail & Related papers  (2021-01-08T19:32:10Z)
• Scalable and Parallel Tweezer Gates for Quantum Computing with Long Ion Strings [1.554996360671779]
  We devise methods to implement scalable and parallel entangling gates by using engineered localized phonon modes. We show that combining our methods with optimal coherent control techniques allows to realize maximally dense universal parallelized quantum circuits.
  arXiv  Detail & Related papers  (2020-08-26T06:01:46Z)
• Computing conditional entropies for quantum correlations [10.549307055348596]
  In particular, we find new upper bounds on the minimal global detection efficiency required to perform device-independent quantum key distribution. We introduce the family of iterated mean quantum R'enyi divergences with parameters $alpha_k = 1+frac12k-1$ for positive integers $k$. We show that the corresponding conditional entropies admit a particularly nice form which, in the context of device-independent optimization, can be relaxed to a semidefinite programming problem.
  arXiv  Detail & Related papers  (2020-07-24T15:27:51Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.