Generation of perfectly entangled two and three qubits states by classical random interaction

Abstract

This study examines the possibility of finding perfect entanglers for a Hamiltonian which corresponds to several quantum information platforms of interest at the present time. However, in this study, we use a superconducting circuit that stands out from other quantum-computing devices, especially because Transmon qubits can be coupled via capacitors or microwave cavities, which enable us to combine high coherence, fast gates, and high flexibility in its design parameters. There are currently two factors limiting the performance of superconducting processors: timing mismatch and the limitation of entangling gates to two qubits. In this work, we present a two-qubit SWAP and a three-qubit Fredkin gate, additionally, we also demonstrate a perfect adiabatic entanglement generation between two and three programmable superconducting qubits. Furthermore, in this study, we also demonstrate the impact of random dephasing, emission, and absorption noises on the quantum gates and entanglement. It is demonstrated by numerical simulation that the CSWAP gate and $W$-state generation can be achieved perfectly in one step with high reliability under weak coupling conditions. Hence, our scheme could contribute to quantum teleportation, quantum communication, and some other areas of quantum information processing.