Physical Review A
One-step generation of cluster states in superconducting charge qubits coupled with a nanomechanical resonator
Gang Chen, Zidong Chen, Lixian Yu, Jiu‐Qing Liang
Abstract
We present a scalable solid-state system in which the superconducting charge qubits are coupled with a nanomechanical resonator (NAMR) to achieve highly entangled cluster states, which are responsible for one-way quantum computing via single-qubit measurements. Since the NAMR can play the essential role of the data bus, the long-range interactions among the qubits can occur. Therefore, without using the interacting picture we can directly obtain the long-range Ising-like unitary operator ${U}_{z}(\ensuremath{\lambda})=\mathrm{exp}[i\ensuremath{\lambda}{S}_{z}^{2}]$ with ${S}_{z}$ the collective spin operator in $z$ direction and $\ensuremath{\lambda}$ a parameter, which is insensitive to the thermal state of the NAMR. Based on this unitary operator, a set of highly entangled cluster states can be produced by efficient one-step generation. Moreover, the robustness of the highly entangled cluster states with respect to unavoidable parameter variations is also demonstrated.