Single atoms coupled to single radiation field modes of a cavity represent the elemental structures in Cavity Quantum Electrodynamics (CQED). Landmark experiments on atoms in cavities have revealed fundamental aspects of coherence in quantum systems and made CQED a central paradigm for the study of open quantum systems. The lack of suitable artificial atoms and cavity technology hindered for a long time the implementation of CQED in solid state. However, constant progresses in crystal growth and nanofabrication have been changing the scenario significantly. In this talk I will show that semiconductor systems can access CQED effects, offering an unprecedented level of control and engineering of light-matter coherent interaction. I will focus on three aspects:
(i) The effective atomic behavior of electrons spatially confined in InAs/GaAs semiconductor self assembled quantum dots (QDs).
(ii) The spatial positioning (Fig 1) and spectral tuning between single QDs and photonic crystals microcavity (PCM) modes.
(iii) The demonstration of a deterministic coupling between single QDs and single PCM modes . I will illustrate the quantum nature of the reached strong-coupling regime  and how the fine structure of the QD is revealed in this regime .
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 K. Hennessy, A. Badolato et al., Nature 445, 896 (2007);
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A. Badolato, M. Winger, et al., C. R. Physique 9 (2008); M. Winger , A. Badolato et al., Phys. Rev. Lett. 103, 207403 (2009).