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arXiv · 1109.4997

Quantum superposition of localized and delocalized phases of photons

Chun-Wang Wu·Ming Gao·Zhi-Jiao Deng·Hong-Yi Dai·Ping-Xing Chen·Cheng-Zu Li
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Abstract

Based on a variant of 2-site Jaynes-Cummings-Hubbard model, which is constructed using superconducting circuits, we propose a method to coherently superpose the localized and delocalized phases of photons. In our model, two nonlinear superconducting stripline resonators are coupled by an interfacial circuit composed of parallel combination of a superconducting qubit and a capacitor, which plays the role of a quantum knob for the photon hopping rate: with the knob qubit in its ground/excited state, the injected photons tend to be localized/delocalized in the resonators. We show that, by applying a microwave field with appropriate frequency on the knob qubit, we could demonstrate Rabi oscillation between photonic localized phase and delocalized phase. Furthermore, this set-up offers advantages (e. g. infinite on/off ratio) over other proposals for the realization of scalable quantum computation with superconducting qubits.

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Chun-Wang Wu, Ming Gao, Zhi-Jiao Deng, Hong-Yi Dai, Ping-Xing Chen, Cheng-Zu Li. 2011-09-23. Quantum superposition of localized and delocalized phases of photons. https://doi.org/10.1016/j.physleta.2012.08.022

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