INVESTIGADORES
CHATTAH Ana Karina
artículos
Título:
NMR Loschmidt echoes as quantifiers of decoherence in interacting spin systems
Autor/es:
CLAUDIA M. SÁNCHEZ; PATRICIA R. LEVSTEIN; RODOLFO H. ACOSTA; ANA K. CHATTAH
Revista:
PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS
Editorial:
The American Physical Society
Referencias:
Año: 2009 vol. 80 p. 123281 - 123287
ISSN:
1050-2947
Resumen:
In this work we present solid -state nuclear magnetic -resonance (NMR) experiments to study decoherence in the dynamics of many-spin systems. We characterize the global Loschmidt echo (LE) and the distribution of multiple -quantum coherence orders during the evolution under dipolar and double -quantum Hamiltonians. To study an infinite 1H system and a closed cluster of nuclear spins we use polycrystalline adamantane and the liquid crystal 5CB in the nematic mesophase,respectively, as model systems. The infinite or finite nature of the system is clearly manifested through spin counting measurements. Comparison between experimental and numerical results gives insights on the decoherence mechanisms in these systems. Contrastingly, the dominating mechanism in 5CB affects all coherence orders in the same way, while in adamantane higher orders of coherence decay faster than the lower ones.