Study on the domain structure and tunable spin orientation in L 1 1 -CoPt/NiFe exchange springs with Ta-spacer

•Effect of tNiFe in L11-CoPt/NiFe(tNiFe) layers with insertion of Ta-spacer was investigated.•Ta-spacer is effective in CoPt/NiFe with two-folds of Hc⊥, and SQR⊥ for tNiFe≥5nm.•A thin 3-nm thick NiFe-layer can produce θM of 45° in L11-CoPt /Ta/NiFe.•Magnetic phase contrast was dominated by topographic feature with increasing tNiFe.•Micromagnetic simulation studies confirmed the existence of tilted magnetic anisotropy.