Heidelberg 2015 – wissenschaftliches Programm
A 4.2: Vortrag
Montag, 23. März 2015, 14:45–15:00, C/HSW
Realizing effective state-dependent optical lattices by periodic driving — Gregor Jotzu, Michael Messer, Frederik Görg, Daniel Greif, •Rémi Desbuquois, and Tilman Esslinger — ETH Zurich, Zurich, Switzerland
Ultracold atoms in optical lattices offer the possibility to engineer specific Hamiltonians, with widely tunable properties. For example, the periodic modulation of the lattice potential yields an effective static Hamiltonian. While previous implementations relied on the physical motion of the lattice potential, this effect can also be realized by periodic modulation of a magnetic field gradient. As the coupling of an atom to this magnetic field gradient depends on its internal state, the effective Hamiltonian is state-dependant. For each internal state, the differing band structure can be characterized either by measuring the ballistic expansion of an atomic cloud in the lattice, or by a measurement of the effective mass through dipole oscillations. This method can be used to create novel situations, such as systems where one state is pinned to the lattice, while the other remains itinerant.