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arXiv · 1207.0088

Large-Scale Schr\"odinger-Cat States and Majorana Bound States in Coupled Circuit-QED Systems

Myung-Joong Hwang·Mahn-Soo Choi
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Abstract

We have studied the low-lying excitations of a chain of coupled circuit-QED systems, and report several intriguing properties of its two nearly degenerate ground states. The ground states are Schr\"odinger cat states at a truly large scale, involving maximal entanglement between the resonator and the qubit, and are mathematically equivalent to Majorana bound states. With a suitable design of physical qubits, they are protected against local fluctuations and constitute a non-local qubit. Further, they can be probed and manipulated coherently by attaching an empty resonator to one end of the circuit-QED chain.

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Myung-Joong Hwang, Mahn-Soo Choi. 2012-06-30. Large-Scale Schr\"odinger-Cat States and Majorana Bound States in Coupled Circuit-QED Systems. https://doi.org/10.1103/physrevb.87.125404

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