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R. Islam, C. Senko, W. C. Campbell, S. Korenblit, J. Smith, A. Lee, E. E. Edwards1, C.-C. J. Wang,, J. K. Freericks and C.Monroe,
Science 340, 583-587 (2013)

Magnetic frustration, the competition between conflicting inter atomic interactions within a many-body
system, is a hallmark feature of many poorly understood yet fascinating systems, such as quantum spin
liquids, spin glasses or spin ices, and is responsible for the complexity of these systems. Cold-atom systems
now offer the possibility of simulating such frustrated systems with exquisite levels of control, as shown by
Islam and colleagues in their paper.

They produce a system of 16 trapped ions, using the Coulomb interactions between the ions to simulate
exchange interactions present in magnetic systems. The measured spin correlations provide a window into
the behaviour of the system, as the effective magnetic field and the range of the interactions are tuned. Their
system approaches the limit where it becomes difficult or impossible to predict its behaviour classically and
can be seen as a prototypical quantum simulation, pointing towards a new probe for the study and design of
quantum frustrated magnets.