A Research Stay on Quantum
Communications between Lisbon and Vigo

From October 1, 2025, to March 31, 2026, Pedro Neto Mendes, a PhD student at Instituto Superior Técnico and a researcher at Instituto de Telecomunicações (Lisbon, Portugal), carried out a six-month research stay at the Vigo Quantum Communication Center (VQCC). During this period, he collaborated primarily with Hannah Thiel and Lukas Tiefenthaler within the Satellite Quantum Communications Hub.

The main focus of his work was the implementation and experimental validation of the Quantum Keyless Private Communication (QKPC) protocol. Initially developed and tested in a controlled laboratory environment, the system was later deployed in a real-world scenario using a 3 km free-space optical link. This enabled investigation of the protocol’s performance under realistic atmospheric conditions, particularly the impact of turbulence on QKPC’s robustness.

This work is particularly relevant in the context of satellite-based quantum communications, where QKPC protocols could serve as a complementary approach to Quantum Key Distribution (QKD). Unlike QKD, QKPC enables the direct transmission of information and can be used in situations where QKD is limited, albeit under different security assumptions.

Beyond the technical contributions, this research stay played an important role in strengthening the collaboration between the quantum communication groups in Lisbon and Vigo. It also contributed significantly to Pedro’s development as an experimental physicist, enhancing his expertise in free-space quantum optics, system deployment, and real-world data analysis.

At the VQCC, we encourage students and researchers interested in similar experiences in quantum technologies to reach out through our contact channels.