Controllable magnon Hanle effect in easy-plane antiferromagnets

Magnon Hanle effect in easy-plane antiferromagnets allows us to obtain different output spin states without switching the Néel vector, which opens up a different path for the construction of future magnonic devices. This effect originates from the precession of the pseudospin and is sensitive to the basic magnetic parameters, such as magnetic anisotropy, so that a precise control of magnon Hanle effect is needed. Here, we manipulate the magnon Hanle effect in easy-plane antiferromagnetic α-Fe2O3 with different film thicknesses and the resultant different strain and easy-plane anisotropy. The Hanle peak shifts to the lower magnetic field when the film thickness increase is associated with decreasing easy-plane anisotropy. The anisotropy–thickness relationship can be attributed to the strain relaxation by interfacial dislocations, which varies with film thickness. Our finding builds a bridge between magnon transport and material microstructures and provides a different perspective for the control of magnon Hanle effect and future magnonic devices.