Emergence of long-range magnetic order stabilized by magnetic impurities in pnictides

Carla Lupo, Thomas Julian Roberts, Cedric Weber
2019 Physical review B  
The Mermin-Wagner theorem prevents the stabilization of long-range magnetic order in two-dimensional layered materials, such as the pnictide superconductors, unless the magnetism is associated with a discrete symmetry breaking. A typical known example is the discrete row and column collinear magnetic state that emerges in doped iron pnictide materials due to an order-by-disorder mechanism. In these compounds, the magnetic state competes with superconductivity and the mechanism that stabilizes
more » ... m that stabilizes magnetism remains controversial. In this work, we report the phase diagram of a doped frustrated Heisenberg model obtained through Monte Carlo simulations combined with a parallel tempering simulation technique. The emergence of long-range magnetic order is stabilized by interactions between the magnetic dopant impurities.
doi:10.1103/physrevb.99.214439 fatcat:t7a6ih7vzrdnzmaxiaqzf6as2q