Focusing characteristics of a 4 πparabolic mirror light-matter interfaceLucas Alber, Martin Fischer, Marianne Bader, Klaus Mantel, Markus Sondermann and Gerd LeuchsJ. Eur. Opt. Soc.-Rapid Publ., 13 1 (2017) 14DOI: https://doi.org/10.1186/s41476-017-0043-y