Remote Entanglement via Adiabatic Passage Using a Tunably Dissipative Quantum Communication System

Area of Science:

• Quantum Information Science
• Superconducting Quantum Computing
• Quantum Communication Systems

Background:

• Effective quantum communication relies on high-fidelity quantum state transfer and remote entanglement generation between quantum nodes.
• Superconducting qubits can be coupled using microwave photons or phonons, but fidelity is often limited by communication channel loss.
• Adiabatic protocols offer a potential solution by enabling quantum state transfer without populating lossy channels.

Purpose of the Study:

• To present and evaluate a unique superconducting quantum communication system utilizing an adiabatic protocol.
• To investigate the system's performance in both low-loss and high-loss communication channel scenarios.
• To compare the adiabatic protocol's efficiency and fidelity against a qubit-resonant mode-qubit relay method.

Main Methods:

• Development of a superconducting quantum communication system with two qubits linked by a 0.73 m channel.
• Introduction of tunable loss into the communication channel to simulate varying environmental conditions.
• Implementation and testing of an adiabatic quantum state transfer protocol.
• Comparison with a qubit-resonant mode-qubit relay method under different loss conditions.

Main Results:

• The adiabatic protocol achieved 99% state transfer efficiency and 96% fidelity for deterministic entangled Bell state generation in a low-loss channel.
• The protocol successfully transferred quantum states without populating the communication channel, outperforming the relay method in high-loss conditions.
• The adiabatic approach demonstrated robustness against channel loss, maintaining higher state transfer and entanglement fidelities compared to the relay method.

Conclusions:

• Adiabatic protocols are highly effective for robust quantum state transfer and entanglement generation in superconducting quantum communication systems.
• The developed system and protocol demonstrate a significant advancement in overcoming channel loss limitations for quantum networks.
• This work provides a viable strategy for building reliable quantum communication links essential for distributed quantum computing and secure communication.