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Quantum Information Processing in Disordered and Complex Quantum Systems

Aditi Sen De·Ujjwal Sen·Veronica Ahufinger·Hans J. Briegel·Anna Sanpera·Maciej Lewenstein
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Abstract

We investigate quantum information processing and manipulations in disordered systems of ultracold atoms and trapped ions. First, we demonstrate generation of entanglement and local realization of quantum gates in a quantum spin glass system. Entanglement in such systems attains significantly high values, after quenched averaging, and has a stable positive value for arbitrary times. Complex systems with long range interactions, such as ion chains or dipolar atomic gases, can be modeled by neural network Hamiltonians. In such systems, we find the characteristic time of persistence of quenched averaged entanglement, and also find the time of its revival.

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Aditi Sen De, Ujjwal Sen, Veronica Ahufinger, Hans J. Briegel, Anna Sanpera, Maciej Lewenstein. 2005-07-18. Quantum Information Processing in Disordered and Complex Quantum Systems. https://doi.org/10.1103/physreva.74.062309

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