Control of domain wall motion at vertically etched nanotrench in ferromagnetic nanowires

We study field-induced domain wall motion in permalloy nanowires with vertically etched nanotrench pinning site. Micromagnetic simulations and electrical measurements are employed to characterize the pinning potential at the nanotrench. It is found that the potential profile for a transverse wall significantly differs from that of a vortex wall, and there is a correlation between the pinning strength and the potential profile. Reliable domain wall pinning and depinning is experimentally observed from a nanotrench in permalloy nanowires. This demonstrates the suitability of the proposed nanotrench pinning sites for domain wall device applications.