The scalable generation of complex entangled photonic states is one of the key challenges in quantum technologies. While bi-partite entangled states have seen substantial progress, achieving high-dimensional and multi-partite entanglement still demands innovative approaches.

A new study, led by the QuCom group at Technische Universität Berlin in collaboration with research teams from Universität Innsbruck, Johannes Kepler Universität Linz, Universidade Estadual de Campinas, Universidad Autónoma de Madrid, and Quandela, has made a significant step forward. The researchers demonstrated how the timed coherent driving of a solid-state three-level system can generate photon states entangled in both time and energy, encoded in the photon-number basis. These findings open doors for quantum networking and dense information encoding.

The Role of Single Quantum’s Detectors

Achieving this level of control and precision required superconducting nanowire single-photon detectors (SNSPDs) from Single Quantum. These detectors were essential for:

✅ Enabling precise control over temporal delays in laser pulse excitation (down to 20 ps).

✅ Resolving single-photon arrival times with high timing resolution.

✅ Maximizing detection efficiency, which is critical for multi-photon correlation experiments.

✅ Minimizing dark counts, ensuring high-fidelity measurements.

As the research team stated:

“Many of the experiments we perform today, especially multi-photon correlation experiments on short timescales, would not be possible without nanowire single-photon detectors like the 12-channel system by Single Quantum we use in our lab.”