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In recent years, quantum memories based on atomic ensembles have been succesfully used to demonstrate a range of key features that are necessary to implement certain quantum communication protocols. One particular type of such memories, sometimes termed deterministic memories, use continuous variable measurements and feedback techniques to achieve a constant storage fidelity in every experimental run. The relevant techniques will be explained and some recent experimental results highlighted. In order to develop such memories into technologically relevant devices, our current work is aimed at integrating similar methods with fibre based microoptics and atomchips. Ideas for experimental realisations, potential benefits, and challenges will be discussed.

I will discuss our recent demonstration of efficient generation of narrow-bandwidth non-classical light in an atomic vapor cell. Using a four-wave mixing process we produce squeezed light as well as heralded single photons and coherent photon superpositions. Employing optical homodyne tomography we fully reconstruct the density matrix of the generated light and verify its non-classical character. Since the heralded states stem from a transient collective spin excitation in the atomic ensemble, this work opens a new possibility of engineering arbitrary superpositions of atomic collective spin excitations.