Quantum computation andW-state generation using superconducting flux qubits coupled to a cavity without geometric and dynamical manipulation

Abstract

Based on superconducting quantum interference devices (SQUID's) coupled to a cavity, we propose a scheme for implementing a quantum phase-shift gate and generating a $W$ state by an adiabatic evolution of dark eigenstates, without any contributions from dynamical and geometric gates. The Sole requirement is of adiabatically increasing or decreasing Rabi frequencies of classical microwave pluses. Thus, the manipulation is robust against certain types of errors. We also analyze the experimental possibility that identical coupling can be achieved between SQUID qubits and cavity fields, and the cavity decay can be ignored in certain conditions. Based on a simple operation, our scheme may be realized in this solid-state system.