Seminarium Optyczne

A proposal [Phys. Rev. Lett. 117, 233001 (2016)] to use a three-level Lambda system to create opticalpotentials for ultracold atoms has lead to effective lattice with subwavelength potential peaks. Thispotential is for atoms that occupy the dark state manifold. The proposal was extended from atomic statesto the bands of Hofstadter-Harper model in a Lambda system configuration. This allows to create a darkstate flat band with Chern number, |C| > 1. Another possible extension of the original work was achievedby considering a four level atomic setup in the tripod configuration which gives an interesting tight-bindingmodel with long range hopping and interaction. Finally, by resonant coupling of many-level system withfields that include random speckle fields, one creates random dark state potentials, that open interestingpossibilities for Anderson localization. In the talk I will present the three above extensions of the originalLambda system.