Preparation of Macroscopic Quantum Superposition States of Cavity Modes Using rf-SQUIDs in a Cavity

We propose a potential scheme of preparing Schrödinger-cat state of the cavity mode by placing an rf-superconducting quantum interference device (rf-SQUID) in a single-mode microwave cavity. By properly adjusting the detuning and the strength regarding the radiation fields, we show how to generate single-mode Schrödinger-cat state. Generalizing this method we discuss the generation of the engtangled coherent states. The experimental feasibility of our scheme is discussed under consideration of the cavity decay.