Institution: | (1) B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, F. Skaryna Ave. 68, 220 072, Minsk, Belarus, BY;(2) Institute of Molecular and Atomic Physics, National Academy of Sciences of Belarus, F. Skaryna Ave. 70, 220 072, Minsk, Belarus, BY;(3) Laboratory for Lasers and Optical Fibres, Sincrotrone-Trieste SS14, km. 163.5, Trieste, Italy, IT;(4) TU Berlin – Optisches Institut, Str. d. 17. Juni 135, 10 623 Berlin, Germany, DE;(5) Institute for Low Temperature and Structure Research, Polish Academy of Sciences, 50-950 Wroclaw 2, PO Box 937, Poland, PL;(6) Vavilov State Optical Institute, Byrzhevaya line 12, 199 034 St.-Petersburg, Russia, RU |