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arXiv · 1203.1857

Nonequilibrium phases in hybrid arrays with flux qubits and NV centers

Thomas Hümmer·Georg M. Reuther·Peter Hänggi·David Zueco
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Abstract

We propose a startling hybrid quantum architecture for simulating a localization-delocalization transition. The concept is based on an array of superconducting flux qubits which are coupled to a diamond crystal containing nitrogen-vacancy (NV) centers. The underlying description is a Jaynes-Cummings-lattice in the strong-coupling regime. However, in contrast to well-studied coupled cavity arrays the interaction between lattice sites is mediated here by the qubit rather than by the oscillator degrees of freedom. Nevertheless, we point out that a transition between a localized and a delocalized phase occurs in this system as well. We demonstrate the possibility of monitoring this transition in a non-equilibrium scenario, including decoherence effects. The proposed scheme allows the monitoring of localization-delocalization transitions in Jaynes-Cummings-lattices by use of currently available experimental technology. Contrary to cavity-coupled lattices, our proposed recourse to stylized qubit networks facilitates (i) to investigate localization-delocalization transitions in arbitrary dimensions and (ii) to tune the inter-site coupling in-situ.

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Thomas Hümmer, Georg M. Reuther, Peter Hänggi, David Zueco. 2012-05-10. Nonequilibrium phases in hybrid arrays with flux qubits and NV centers. https://doi.org/10.1103/physreva.85.052320

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