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arXiv · 2407.05902

Towards Photon-Number-Encoded High-dimensional Entanglement from a Sequentially Excited Quantum Three-Level System

Daniel A. Vajner·Nils D. Kewitz·Martin von Helversen·Stephen C. Wein·Yusuf Karli·Florian Kappe·Vikas Remesh·Saimon F. Covre da Silva·Armando Rastelli·Gregor Weihs·Carlos Anton-Solanas·Tobias Heindel
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Abstract

The sequential resonant excitation of a 2-level quantum system results in the emission of a state of light showing time-entanglement encoded in the photon-number-basis - notions that can be extended to 3-level quantum systems as discussed in a recent proposal. Here, we report the experimental implementation of a sequential two-photon resonant excitation process of a solid-state 3-level system, constituted by the biexciton-, exciton-, and ground-state of a semiconductor quantum dot. The resulting light state exhibits entanglement in time and energy, encoded in the photon-number basis, which could be used in quantum information applications, e.g., dense information encoding or quantum communication protocols. Performing energy- and time-resolved correlation experiments in combination with extensive theoretical modelling, we are able to partially retrieve the entanglement structure of the generated state.

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Daniel A. Vajner, Nils D. Kewitz, Martin von Helversen, Stephen C. Wein, Yusuf Karli, Florian Kappe, Vikas Remesh, Saimon F. Covre da Silva, Armando Rastelli, Gregor Weihs, Carlos Anton-Solanas, Tobias Heindel. 2024-07-08. Towards Photon-Number-Encoded High-dimensional Entanglement from a Sequentially Excited Quantum Three-Level System. https://doi.org/10.1364/opticaq.538134

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