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arXiv · 1711.11490

Microscopic theory of cavity-enhanced single-photon emission from optical two-photon Raman processes

Dominik Breddermann·Tom Praschan·Dirk Heinze·Rolf Binder·Stefan Schumacher
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Abstract

We consider cavity-enhanced single-photon generation from stimulated two-photon Raman processes in three-level systems. We compare four fundamental system configurations, one $Λ$-, one V- and two ladder ($Ξ$-) configurations. These can be realized as subsystems of a single quantum dot or of quantum-dot molecules. For a new microscopic understanding of the Raman process, we analyze the Heisenberg equation of motion applying the cluster-expansion scheme. Within this formalism an exact and rigorous definition of a cavity-enhanced Raman photon via its corresponding Raman correlation is possible. This definition for example enables us to systematically investigate the on-demand potential of Raman-transition-based single-photon sources. The four system arrangements can be divided into two subclasses, $Λ$-type and V-type, which exhibit strongly different Raman-emission characteristics and Raman-emission probabilities. Moreover, our approach reveals whether the Raman path generates a single photon or just induces destructive quantum interference with other excitation paths. Based on our findings and as a first application, we gain a more detailed understanding of experimental data from the literature. Our analysis and results are also transferable to the case of atomic three-level-resonator systems, and can be extended to more complicated multi-level schemes.

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Dominik Breddermann, Tom Praschan, Dirk Heinze, Rolf Binder, Stefan Schumacher. 2018-03-13. Microscopic theory of cavity-enhanced single-photon emission from optical two-photon Raman processes. https://doi.org/10.1103/physrevb.97.125303

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