Investigating the influence of the depinning energy barrier on domain wall motion in perpendicularly magnetized Pt/Co/Cr/Ta multilayers

•We study the influence of the depinning energy barrier on DW motion in the creep regime using the magneto-optical Kerr microscopy in the Cr layer decorated Pt/Co/Ta structure.•The results show that although the SOT efficiency has been enhanced in Pt/Co/Cr/Ta structure, but its current-induced DW motion efficiency still shows an attenuation. The unexpected results can be ascribed to the enhanced depinning energy barrier in Pt/Co/Cr/Ta structure.