Hybrid-variable microwave quantum communication over thermal channels

• Applicant: Dr. Kirill Fedorov
• Subject Area: Experimental Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 573275578

Microwave quantum networks are set to play an important role in the future quantum science and technology. They can be utilized as a versatile experimental platform for fundamental studies of quantum correlations in the presence of noise and non-Markovian effects caused by large signal delays. From the applied point of view, such networks enable distributed quantum computing architectures with superconducting circuits, thus, addressing the central scalability issue of modern quantum computers. In this project, we propose experimental studies of microwave thermal networks in the quantum, hybrid-variable, regime. The latter is outlined by the combination of continuous-variable, squeezed vacuum states and discrete-variable, Fock states. The corresponding propagating microwave states can be generated by superconducting parametric amplifiers and transmon qubits. The combination of these two different information-encoding approaches potentially allows to overcome fundamental limits of quantum communication imposed by losses and noise in microwave networks operated at elevated temperatures. The experimental demonstration of related entanglement distribution and distillation protocols, as well as hybrid-variable microwave quantum teleportation, over thermal channels represents main milestones of the current project. Its success will bring forward new fundamental understanding of nonlocal quantum physics in nonequilibrium, noisy networks and set the path towards distributed superconducting quantum systems.

• DFG Programme: Research Grants