Heidelberg 2015 – wissenschaftliches Programm
A 17.6: Vortrag
Dienstag, 24. März 2015, 15:45–16:00, P/H1
Optical Bloch band spectroscopy with laser cooled magnesium atoms — •André Kulosa, Steffen Rühmann, Dominika Fim, Klaus Zipfel, Nandan Jha, Steffen Sauer, Wolfgang Ertmer, and Ernst Rasel — Leibniz Universität Hannover, Institut für Quantenoptik, Hannover
Here we report on optical Bloch band spectroscopy of laser cooled magnesium atoms trapped in a magic wavelength lattice. Phenomena observed with atoms in lattices show close analogies to those known for electrons in solid state physics as the periodic light field potential can be directly related to a periodic crystal structure. Moreover, tunneling between the lattice sites leads to delocalization of atoms with a resulting band structure in the atomic energy spectrum. We employ spectroscopy of the band structure to gather information about the atomic polarizabilities of the involved electronic states.
Atoms are probed on the spin-forbidden 1S0→ 3P0 clock transition at 458 nm with a spectroscopic linewidth of about 3 kHz. Lowering the trap depth to less than 10 recoil energies, we expect a bandwidth resulting from the energy dispersion of the lower and upper band to be larger than the spectroscopic linewidth and a line shape reflecting the band structure of the lower and upper electronic state. For an increasing trap depth and as a consequence a decreasing ground state bandwidth, we see the corresponding decreasing in the carrier frequency shift as it has been postulated by P. Wolf and P. Lemonde .
 P. Lemonde and P. Wolf, Phys. Rev. A 72, 033409 (2005)