Chirality-selection of magnetic domain walls in the Y-shaped nanostrips under small magnetic fields

•Two types of Y-shaped junctions exhibit much lower DW transmission fields.•The magnetic charges in corners and junction are responsible for these behaviors.•The control of DW chirality allows Y-shaped junctions to perform as logic devices. The chirality-dependent propagations of transverse domain walls (DWs) in two types of Y-shaped nanostrips under small driving fields were investigated using micromagnetic simulations. They both exhibit the well DW chirality selection behaviors and the hugely reduced DW transmission fields owing to the specific magnetic charge distributions on both the junction and corners. The DW transmission field even can be as small as 2 Oe. Additionally, the DW chirality can be controlled by applying an out-of-plane field, leading to the use of the Y-shaped nanostrips as logic devices, such as selector, rectifier and amplifier.