Quantum-correlated photons in semiconductor micropillars enabled by two-color excitation

• Applicant: Dr. Christian Kriso
• Subject Area: Experimental Condensed Matter Physics ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 540117239

Realizing a scalable solid-state platform with strong photon-photon interactions that lead to pronounced quantum correlations of the emitted photons has been a long-standing goal of solid-state quantum optics. Exciton-polaritons, hybridized quasi-particles consisting of a photon and a semiconductor exciton strongly coupled in a high-Q cavity, are a prime candidate for the realization of this objective due to their inherent scalability and their large nonlinearity stemming from the excitonic component. However, up to know, only very weak antibunching, the hallmark of strong photon-photon interactions, has been observed from spatially confined exciton-polaritons. This project aims to make an important step towards generating significant quantum correlations from exciton-polaritons hosted in semiconductor micropillars by making use of a novel non-degenerate two-color excitation scheme that is expected to boost the effective polariton interaction strength and which will also be used to measure precisely the polariton interaction energy at the quantum level. This scheme will not only be applied to currently existing micropillar samples with a single quantum well but also to a new generation of samples with two coupled quantum wells that host dipolar excitons/polaritons expected to have a larger intrinsic interaction strength, and to single micropillars as well as two coupled micropillars. The successful implementation of the project will open the door to studying polariton physics beyond the mean-field regime and, in the long-term, to realizing extended lattices of strongly-interacting photons, a crucial resource for applications in quantum simulation and technology.

• DFG Programme: WBP Fellowship
• International Connection: France
• Host: Dr. Sylvain Ravets