Symmetry breaking

Quantum mechanics

Magnetic field

Spin (aerodynamics)

Chemical physics

Magnetization

Antiferromagnetism

Metallurgy

Materials science

Frustration

Ferromagnetism

Coupling (piping)

Degenerate energy levels

Thermodynamics

Physics

Mathematics

Work (physics)

Spin glass

Condensed matter physics

Geometry

Exchange bias

Symmetry (geometry)

Magnetic anisotropy

Spintronics

Nature Physics

The interplay of symmetry and quenched disorder leads to some of the most fundamentally interesting and technologically important properties of correlated materials. It also poses the most vexing of theoretical challenges. Nowhere is this more apparent than in the study of spin glasses. A spin glass is characterized by an ergodic landscape of states - an innumerable number of possibilities that are only weakly distinguished energetically, if at all. We show in the material Fe$_x$NbS$_2$, this landscape of states can be biased by coexisitng antiferromagnetic order. This process leads to a phenomenon of broad technological importance: giant, tunable exchange bias. We observe exchange biases that exceed those of conventional materials by more than two orders of magnitude. This work illustrates a novel route to giant exchange bias by leveraging the interplay of frustration and disorder in exotic materials.

Exchange bias due to coupling between coexisting antiferromagnetic and spin-glass orders