Magnetic Field Switching of Exchange Bias in a Metallic FM/AFM Heterostructure at Room Temperature.

Abstract

The exchange bias effect, which causes a shift in the ferromagnetic hysteresis loop due to magnetic coupling with an adjacent antiferromagnetic layer, has been a key area of study for fundamental research and spintronic applications. This effect is known to be static once established through a field cooling procedure and is difficult to manipulate isothermally. Here we present the first room temperature field switching of interlayer magnetic coupling at the metallic heterointerface between a ferromagnet and antiferromaget. Specifically, we demonstrate that the exchange bias can be systematically switched by manipulating the global time-reversal-symmetry-broken antiferromagnetic order of Mn₃Sn via both magnetic field sweeping and field cooling. Furthermore, we confirm that the magnitude and sign of the interlayer coupling can be tuned by selecting the ferromagnet. These findings provide a novel approach for controlling the magnetic state of ferromagnets and functional antiferromagnets, paving the way for advancing spintronic technologies using antiferromagnets.