Seminar
Tuesday, 23 November, 2010
Group Seminar LMU: Control and detection of spin-spin correlations in optical superlattices
Tuesday, 23.11.2010 10 a.m. (s.t.) in H107, Fakultät für Physik LMU
Stefan Trotzky
Being able to control and detect finite-range spin-spin correlations is a key requirement for the study of quantum magnets of ultracold atoms in optical lattices. We use a bichromatic superlattice to engineer an array of effective spin triplet pairs of bosons on neighboring sites. These triplets are converted into singlets by means of a magnetic field gradient. We are able monitor the gradient-driven singlet-triplet oscillations by mapping the parity of the local spin-wave function onto the parity of single-site spatial orbitals. The introduction of local superexchange oscillations prior to the detection effectively allows to measure spin-spin correlations over a larger distance.
In this seminar, I will give a technical introduction to our realization of a bichromatic superlattice befor turning to spin-spin correlations. We will discuss how the detection method can be extended to fermions as well as to single-site resolved measurements.