Multiple Quantum Coherence and Decoherence in a Restricted Hilbert Space

E. RUFEIL FIORI; F. OLIVA; C. M. SÁNCHEZ; H. M. PASTAWSKI; P. R. LEVSTEIN

Córdoba

Congreso; Mini-School on Disordered Systems 2008 and 6th International Workshop on Disordered System; 2008

LaNAIS, Facultad de Matemática, Astronomía y Física, Universidad Nacional de Córdoba.

In this work, we test the one-body dynamics in a network of coupled spins using solid state nuclear magnetic resonance. In particular, one can generate an effective double quantum Hamiltonian (flip-flip + flop-flop) that mixes subspaces with different spin projection creating many-body superposition states: the multiple quantum coherences. These states can be probed through a bidimensional technique that allows one to follow the superposition weights as they are created. Multiple-quantum coherence intensities are measured under a double-quantum Hamiltonian in hydroxyapatite. This system is a quasi-one-dimensional spin chain, as the distance between hydrogen spin chains is about three times larger than the distance between adjacent protons within the chain. As a consequence of the distance dependence of the dipolar interaction and the quantum Zeno effect, this should lead to a separation in about three orders of magnitude between the intra and inter-chain time scales.