Free-Electron Quantum Optics

Until recently, work in quantum optics focused on light interacting with bound-electron systems such as atoms, quantum dots, and nonlinear optical crystals. In contrast, free-electron systems enable fundamentally different physical phenomena, as their energy distribution is continuous and not discrete, allowing for tunable transitions and selection rules.

Recent theoretical and experimental breakthroughs involving quantum interactions of free electrons spawned an exciting new field: free-electron quantum optics. We developed a platform for exploring free-electron quantum optics at the nanoscale, and used it to demonstrate the first coherent interaction of a free electron with a photonic cavity and with the quantum statistics of photons.

These capabilities open new paths toward using free electrons as carriers of quantum information. Free electrons emerge as quantum optical sources for desired photonics states used in fault-tolerant quantum computation and communication such as Schrodinger cat states and GKP states.

Concepts of quantum optics with free electrons also promote new modalities in electron microscopy. We demonstrated the first instance of coherent amplification in electron microscopy. Our vision is to develop a microscope that can image coherence, going beyond conventional imaging of matter to also image the coherent quantum state of matter and probe quantum correlations between individual quantum systems.

1. Rivera and I. Kaminer, Light–matter interactions with photonic quasiparticles, Nature Reviews Physics 2, 538–561 (2020) (Review)
2. Wang, R. Dahan, M. Shentcis, Y. Kauffmann, A. Ben-Hayun, O. Reinhardt, S. Tsesses, I. Kaminer, Coherent Interaction between Free Electrons and Cavity Photons, Nature 582, 50 (2020)
3. Ruimy†, A. Gorlach†, C. Mechel, N. Rivera, and I. Kaminer, Towards atomic-resolution quantum measurements with coherently-shaped free electrons, Phys. Rev. Lett. 126, 233403 (2021)
4. Reinhardt†, C. Mechel†, M. H. Lynch, and I. Kaminer, Free-Electron Qubits, Annalen der Physik 533, 2000254 (2021)
5. Kurman†, R. Dahan†, H. Herzig Shenfux, K. Wang, M. Yannai, Y. Adiv, O. Reinhardt, L. H. G. Tizei, S. Y. Woo, J. Li, J. H. Edgar, M. Kociak, F. H. L. Koppens, and I. Kaminer, Spatiotemporal imaging of 2D polariton wavepacket dynamics using free electrons, Science 372, 1181 (2021)
6. Dahan†, A. Gorlach†, U. Haeusler†, A. Karnieli†, O. Eyal, P. Yousefi, M. Segev, A. Arie, G. Eisenstein, P. Hommelhoff, and I. Kaminer, Imprinting the quantum statistics of photons on free electrons, Science 373, 6561 (2021)
7. Karnieli†, S. Tsesses†, R. Yu†, N. Rivera, Z. Zhao, A. Arie, S. Fan, and I. Kaminer, Quantum sensing of strongly coupled light-matter systems using free electrons, Science Advances 9, add2349 (2023)
8. Dahan†, G. Baranes†, A. Gorlach, R. Ruimy, N. Rivera, and I. Kaminer, Creation of Optical Cat and GKP States Using Shaped Free Electrons, PRX 13, 031001 (2023)
9. Bucher et al., Coherently amplified ultrafast imaging in a free-electron interferometer, arXiv:2305.04877

Seminar realized in the framework of the funded projects:
SMART-electron project  grant agreement no. 964591.