Thermal Influence on Chirality-Driven Dynamics and Pinning of Transverse Domain Walls in Z-Junction Magnetic Nanowires

Magnetic nanowires with domain walls (DWs) play a crucial role in the advancement of next-generation memory and spintronic devices. Understanding the thermal effects on domain wall behavior is essential for optimizing performance and stability. This study investigates the thermal chirality-dependent dynamics and pinning of transverse domain walls (TDWs) in Z-junction nanowires using micromagnetic simulations. The analysis focuses on head-to-head (HHW) and tail-to-tail (TTW) domain walls with up and down chirality under varying thermal conditions. The results indicate that higher temperatures reduce the pinning strength and depinning current density, leading to enhanced domain wall velocity. At 200 K, the HHWdown domain wall depins at a critical current density of 1.2 × 1011 A/m2, while HHWup requires a higher depinning temperature, indicating stronger pinning effects. Similarly, the depinning temperature (Td) increases with Z-junction depth (d), reaching 300 K at d = 50 nm, while increasing Z-junction (λ) weakens pinning, reducing Td to 150 K at λ = 50 nm. Additionally, the influence of Z-junction geometry and magnetic properties, such as saturation magnetization (Ms) and anisotropy constant (Ku), is examined to determine their effects on thermal pinning and depinning. These findings highlight the critical role of chirality and thermal activation in domain wall motion, offering insights into the design of energy-efficient, high-speed nanowire-based memory devices.