1. National Institute of Standards and Technology, Boulder, Colorado 80305, USA
2. University of Colorado, Boulder, Colorado 80309-0440, USA
3. FEMTO-ST, CNRS, 26 rue de l'épitaphe 25030 Besancon, France
4. Novosibirsk State University, ul. Pirogova 2, Novosibirsk 630090, Russia
5. Institute of Laser Physics SB RAS, pr. Akademika Lavrent'eva 13/3, Novosibirsk 630090, Russia
6. Novosibirsk State Technical University, pr. Karla Marksa 20, Novosibirsk 630073, Russia