Anisotropy‐Driven Stripe Domain Behavior in Ni–Cr Thin Films: Insights at Remanence

By harnessing electron spin as well as charge, spintronic materials offer ultra‐efficient memory, logic, and sensing technologies with strong potential for AI and quantum applications. Understanding how magnetic domain textures and their dynamics evolve at remanence with thickness is essential for engineering reconfigurable spintronic materials. Here, micromagnetic simulations of Ni–Cr thin films (10–100 nm) accurately reproduce the stripe‐domain patterns observed by magnetic force microscopy, including a characteristic domain width of ∼150 nm in 40 nm films, supported by a perpendicular anisotropy of K p ≈ 75 kJ/m 3 . Simulated hysteresis loops reveal a transition from conventional in‐plane reversal in 10–20 nm films to transcritical behavior above ∼ 40 nm, driven by the emergence of perpendicular magnetic anisotropy (PMA). Broadband ferromagnetic resonance (FMR) measurements (2–18 GHz) further show a thickness‐dependent evolution of dynamics: a single uniform mode in thin films, mode splitting at 40 nm, and strong perpendicular standing spin‐wave (PSSW) modes in 100 nm films, consistent with simulated remanent‐state resonances of ∼1.1–2.4 GHz. Kittel analysis yields 4 π M eff ≈ 1462 G and an anisotropy field of H k = −194 Oe in thinner films, with a sign reversal to positive H k at larger thicknesses, confirming the onset of PMA. These results link remanent‐domain morphology, reversal mechanisms, and GHz spin dynamics, demonstrating the tunability of Ni–Cr films for spintronic and magnonic applications.