Mechanical tuning of room temperature magnetism in flexible manganite/mica heterostructures

Abstract

Flexible materials have attracted increasing attention due to their potential application in wearable or implantable circuits and systems. Here, the La0.67Sr0.33MnO3 (LSMO) thin films have been grown on single crystalline mica substrates and the impact of mechanical strain on the magnetic properties is investigated through varying external mechanical bending. The in-plane saturated magnetic moment decreases firstly with increasing radius of curvature (ROC) and then increases after attaining a minimum value of MS = 187 emu/cm3 at ROC = 3.0 mm. The nonmonotonous dependence of magnetic moment on ROC can be attributed to the mechanical bending-triggered lateral tensile strain, which can not only enhance the Jahn-Teller splitting and reduce the double-exchange interaction, but also enable the neighboring ferromagnetic domain switching in the LSMO films. Moreover, the out-of-plane magnetic anisotropy can also be reinforced by exerting mechanical tensile strain. Meanwhile, the superior mechanical antifatigue character is found in the LSMO/mica structures. These flexible LSMO thin films with highly tunable magnetism and excellent mechanical durability exhibit promising prospect in designing stable flexible spintronic devices and wearable sensors.