Emergent Magnetism as a Cooperative Effect of Interactions and Reservoir.

Closed shell molecular structures are under normal conditions time-reversal invariant. Experimental evidence points, however, toward that this invariance may be locally violated when the structure is in contact with a particle reservoir. The mechanisms behind such local symmetry breaking are not clear by any means.

Monolayer CrCl_{3} as an Ideal Test Bed for the Universality Classes of 2D Magnetism.

The monolayer halides CrX_{3} (X=Cl, Br, I) attract significant attention for realizing 2D magnets with genuine long-range order (LRO), challenging the Mermin-Wagner theorem. Here, we show that monolayer CrCl_{3} has the unique benefit of exhibiting tunable magnetic anisotropy upon applying a compressive strain. This opens the possibility to use CrCl_{3} for producing and studying both ferromagnetic and antiferromagnetic 2D Ising-type LRO as well as the Berezinskii-Kosterlitz-Thouless (BKT) regime of 2D magnetism with quasi-LRO.