Flexomagnetism and vertically graded Néel temperature of antiferromagnetic Cr2O3 thin films

Thin films of antiferromagnetic insulators are a prospective material platform for magnonics, spin superfluidity, THz spintronics, and nonvolatile data storage. Here, we explore the presence of flexomagnetic effects in epitaxial Cr2O3 [1]. We demonstrate that a gradient of mechanical strain effect the order-disorder magnetic phase transition, resulting in the distribution of the Néel temperature along the thickness of a Cr2O3 film. The inhomogeneous reduction of the antiferromagnetic order parameter induces a flexomagnetic coefficient of about 15µB nm−2. The antiferromagnetic ordering in the strained films can persist up to 100∘C, rendering Cr2O3 as a prospective material for industrial electronics applications.