Protocol of a quantum walk in circuit QED
Jiaqi Zhou, Ling Cai, Qi-Ping Su, Chui‐Ping Yang · Physical Review A · 2019
Implementation of a discrete-time quantum walk (DTQW) with superconducting qubits is difficult since on-chip superconducting qubits cannot hop between lattice sites. We propose an efficient protocol for the implementation of DTQW in circuit quantum electrodynamics (QED), in which only $N+1$ qutrits, $N$ cavities, and other assistant devices are needed for an $N$-step DTQW. The operation of each DTQW step is very quick because only resonant processes are adopted. The numerical simulations show that high-similarity DTQW with a number of steps up to 20 is feasible with present-day circuit QED techniques. This protocol can help to study properties and applications of many-step DTQW in experiments, and can be extended to implement multidimensional DTQW in circuit QED or other quantum systems.