Guido van de Stolpe

All Publications

• Toward quantum sensing of electron beams using solid-state spins. Proceedings of the National Academy of Sciences of the United States of America Grzesik, J. M., Catanzaro, D., Roques-Carmes, C., Rosenthal, E. I., van de Stolpe, G. L., Karnieli, A., Scuri, G., Biswas, S., Leedle, K. J., Black, D. S., Byer, R. L., Kaminer, I., England, R. J., Fan, S., Solgaard, O., Vučković, J. 2026; 123 (25): e2531808123

  Abstract

  Scattering experiments with energetic particles, such as free electrons, have been historically used to reveal the quantum structure of matter. However, realizing coherent interactions between free-electron beams and solid-state quantum systems has remained out of reach, owing to their intrinsically weak coupling. Realizing such coherent control would open up opportunities for hybrid quantum platforms combining free electrons and solid-state qubits for coincident quantum information processing and nanoscale sensing. Here, we present a framework that employs negatively charged nitrogen-vacancy centers (NV-) in diamond as quantum sensors of a bunched electron beam. We develop a Lindblad master equation description of the magnetic free-electron-qubit interactions and identify spin relaxometry as a sensitive probe of the interaction. Experimentally, we integrate a confocal fluorescence microscopy setup into a microwave-bunched electron beam line. We monitor charge-state dynamics and assess their impact on key sensing performance metrics (such as spin readout contrast), defining safe operating parameters for quantum sensing experiments. By performing [Formula: see text] relaxometry under controlled electron beam exposure, we do not resolve a measurable reduction in [Formula: see text] within experimental uncertainty, and instead establish an upper bound on the free-electron-spin coupling strength. Our results establish NV- centers as quantitative probes of free electrons, providing a metrological benchmark for free-electron-qubit coupling under realistic conditions, and chart a route toward solid-state quantum control with electron beams.

  View details for DOI 10.1073/pnas.2531808123

  View details for PubMedID 42284299

• Sub-kHz mechanical resonator passively cooled to 6 mK PHYSICAL REVIEW RESEARCH van Everdingen, L., Plugge, J., Fuchs, T. M., van de Stolpe, G. L., Benali, D., de Jong, T., Bijl, J., Bosch, W. A., Oosterkamp, T. H. 2026; 8 (2)

  View details for DOI 10.1103/jmyg-299x

  View details for Web of Science ID 001744833000001

• Improved Electron-Nuclear Quantum Gates for Spin Sensing and Control PRX QUANTUM van Ommen, H. B., van de Stolpe, G. L., Demetriou, N., Beukers, H. C., Yun, J., Fortuin, T. J., Iuliano, M., Montblanch, A., Hanson, R., Taminiau, T. H. 2025; 6 (2)

  View details for DOI 10.1103/PRXQuantum.6.020309

  View details for Web of Science ID 001472004400001

• Check-probe spectroscopy of lifetime-limited emitters in bulk-grown silicon carbide NPJ QUANTUM INFORMATION van de Stolpe, G. L., Feije, L. J., Loenen, S. H., Das, A., Timmer, G. M., de Jong, T. W., Taminiau, T. H. 2025; 11 (1): 31

  Abstract

  Solid-state single-photon emitters provide a versatile platform for exploring quantum technologies such as optically connected quantum networks. A key challenge is to ensure the optical coherence and spectral stability of the emitters. Here, we introduce a high-bandwidth 'check-probe' scheme to quantitatively measure (laser-induced) spectral diffusion and ionisation rates, as well as homogeneous linewidths. We demonstrate these methods on single V2 centres in commercially available bulk-grown 4H-silicon carbide. Despite observing significant spectral diffusion under laser illumination (≳GHz s-1), the optical transitions are narrow (~35 MHz), and remain stable in the dark (≳1 s). Through Landau-Zener-Stückelberg interferometry, we determine the optical coherence to be near-lifetime limited (T 2 = 16.4(4) ns), hinting at the potential for using bulk-grown materials for developing quantum technologies. These results advance our understanding of spectral diffusion of quantum emitters in semiconductor materials, and may have applications for studying charge dynamics across other platforms.

  View details for DOI 10.1038/s41534-025-00985-3

  View details for Web of Science ID 001428617800001

  View details for PubMedID 39996104

  View details for PubMedCentralID PMC11846708