Radiation-induced interaction potential of two qubits strongly coupled with a quantized electromagnetic field

Abstract

We investigate the interaction of two two-level qubits with a single-mode quantum field in a cavity without the rotating wave approximation and considering that qubits can be located at an arbitrary distance from each other. We demonstrate that there exists a radiation-induced interaction potential between atoms. We studied the properties of the system numerically and in addition constructed a simple analytical approximation. It is shown that the observable characteristics are substantially dependent on the distance between the qubits in the strong-coupling regime. This allows one to perform the quantum control of the qubits, which can be exploited for the recording and transmission of quantum information.