Heterogeneous cluster size distribution of coherences in the quantum dynamics of an infinite spin ½ system.

C.M. SANCHEZ; R.H. ACOSTA; A.K. CHATTAH; P.R. LEVSTEIN

Angra dos Reis

Congreso; 13th Nuclear Magnetic Resonance Users Meeting; 2011

The study of generation, evolution, and control of coherent quantum dynamics in large Hilbert spaces has drawn much theoretical and experimental attention over the last years due to the direct application on, for instance, quantum information processing1. The main drawback on the implementation of quantum registers arises from the degradation of the correlation between states due to interactions with the environment. This process is generally known as decoherence and it determines how much information can be transmitted from one quantum manipulation to the next. In previous works, we studied the decoherence that occurs during the evolution of dipolar coupled nuclear spin systems using solid state NMR2,3. In particular, we measured spin ½ systems in an infinite network with only intermolecular interactions (adamantane), other with only intramolecular interactions (5CB) and one with both intra and intermolecular interactions (ferrocene). The loss of information, or decoherence, can be quantified through the Loschmidt echo (LE) which is generated by reverting the time evolution of the system. For this work, we implemented a sequence to make the systems evolve under HDQ (Ij+ Ik++ Ij- Ik-). After the experimental observation of a striking distribution of coherence orders found in adamantane shown in Figure 1, we analyzed in detail the formation of different sized clusters and their evolutions under HDQ.