Golonko P, Kašík I, Mrázek J, Żmojda J. Influence of ZnF2 concentration on excitation energy transfer between Er3+ and Tm3+ ions in antimony-germanate glass ceramic . Photonics Lett. Pol. [Internet]. 2024 Apr. 2 [cited 2024 Dec. 27];16(1):4-6. Available from: https://photonics.pl/PLP/index.php/letters/article/view/16-2