Entanglement-storage units

We introduce a protocol based on optimal control to drive many-body quantum systems into long-lived entangled states, protected from decoherence by large energy gaps, without requiring any a priori knowledge of the system. With this approach it is possible to implement scalable entanglement-storage units. We test the protocol in the Lipkin?Meshkov?Glick model, a prototype many-body quantum system that describes different experimental setups, and in the ordered Ising chain, a model representing a possible implementation of a quantum bus.

[1]  F. C. Alcaraz,et al.  Entanglement of low-energy excitations in conformal field theory. , 2011, Physical review letters.

[2]  Christine Guerlin,et al.  Dicke quantum phase transition with a superfluid gas in an optical cavity , 2009, Nature.

[3]  Aharonov,et al.  Geometry of quantum evolution. , 1990, Physical review letters.

[4]  Dynamical imperfections in quantum computers , 2004, quant-ph/0407098.

[5]  V. Vedral,et al.  Entanglement in many-body systems , 2007, quant-ph/0703044.

[6]  S. Dusuel,et al.  Entanglement entropy beyond the free case. , 2006, Physical Review Letters.

[7]  J. Latorre,et al.  Entanglement entropy in the Lipkin-Meshkov-Glick model (4 pages) , 2004, cond-mat/0409611.

[8]  G. Vidal,et al.  Entanglement in quantum critical phenomena. , 2002, Physical review letters.

[9]  Artur Ekert,et al.  Quantum computers and dissipation , 1996, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[10]  P. Calabrese,et al.  Entanglement entropy of excited states , 2009, 0909.1999.

[11]  H. Lipkin,et al.  Validity of many-body approximation methods for a solvable model: (I). Exact solutions and perturbation theory , 1965 .

[12]  P. Zanardi,et al.  Noiseless Quantum Codes , 1997, quant-ph/9705044.

[13]  Ulrich Hohenester,et al.  Twin-atom beams , 2010, 1012.2348.

[14]  W. Wootters Entanglement of Formation of an Arbitrary State of Two Qubits , 1997, quant-ph/9709029.

[15]  J. Vidal,et al.  Exact spectrum of the Lipkin-Meshkov-Glick model in the thermodynamic limit and finite-size corrections. , 2008, Physical review. E, Statistical, nonlinear, and soft matter physics.

[16]  Robert Botet,et al.  Large-size critical behavior of infinitely coordinated systems , 1983 .

[17]  Marcel Novaes,et al.  Resonances in open quantum maps , 2012, 1211.7248.

[18]  I. Chuang,et al.  Quantum Computation and Quantum Information: Introduction to the Tenth Anniversary Edition , 2010 .

[19]  Andreas Buchleitner,et al.  Optimal dynamical control of many-body entanglement. , 2010, Physical review letters.

[20]  Tommaso Calarco,et al.  Chopped random-basis quantum optimization , 2011, 1103.0855.

[21]  Tommaso Calarco,et al.  Optimal control technique for many-body quantum dynamics. , 2010, Physical review letters.

[22]  Guang-Can Guo,et al.  Preserving Coherence in Quantum Computation by Pairing Quantum Bits , 1997 .