Growth-temperature dependence of morphology and magnetism in Cr(001) films revealed via spin-polarized scanning tunneling microscopy

Abstract We investigate the surface morphology and magnetic properties of 6-nm-thick Cr films prepared by first depositing a 2-nm-thick Cr layer at 290 K, followed by an additional 4-nm-thick layer deposited at 570, 620, and 670 K. Magnetic images of these Cr films, together with their topographic images, are obtained at 290 K via spin-polarized scanning tunneling microscopy. Our results show that surface morphology and magnetism of the Cr films depend significantly on the growth temperatures due to increasing screw dislocation density. Distinct magnetic contrasts featuring a layered antiferromagnetic (LAF) order are observed in the films grown at 570 and 620 K; however, different types of spin frustrations are observed. Two equivalent domains of the LAF order in the 〈100〉 direction are formed in the films grown at 620 and 670 K, which dissolve complex spin frustration. These findings may be important to advance spin electronics using AF films.