Growth and mid-infrared emission properties of "mixed" fluorite-type Er:(Ca,Sr)F2 and Er:(Ba,Sr)F2 crystalsLiza Basyrova, Pavel Loiko, Abdelmjid Benayad, Gurvan Brasse, Jean-Louis Doualan, Alain Braud, Ammar Hideur and Patrice CamyEPJ Web Conf., 266 (2022) 06001DOI: https://doi.org/10.1051/epjconf/202226606001