Establishing spin-network topologies by repeated projective measurements

Abstract

It has been recently shown that in quantum systems, the complex time evolution typical of many-bodied coupled networks can be transformed into a simple, relaxation-like dynamics, by relying on periodic dephasings of the off-diagonal density matrix elements. This represents a case of "quantum Zeno effects", where unitary evolutions are inhibited by projective measurements. We present here a novel exploitation of these effects, by showing that a relaxation-like behaviour is endowed to the polarization transfers occurring within a N-spin coupled network. Experimental implementations and coupling constant determinations for complex spin-coupling topologies, are thus demonstrated within the field of liquid-state nuclear magnetic resonance (NMR).