Electric field control for energy efficient domain wall injection

Abstract Domain wall injection by electric means is an energy exhausting process. This process is conventionally carried out by sending a current pulse through a stripline which generates an Oersted field to locally switch the magnetization in a magnetic wire. In this work, the magnetic properties of the device were modulated by electric control to lower the required current density for DW injection. The proposed DW injection device employs a Hall cross structure which simplifies the device fabrication process and allows a larger Oersted field to be generated at the domain wall injection region. Electrical pulses of 50 ns were sent through the Hall bar to inject domain walls. The formation of the resulting domain walls was detected electrically using the Hall resistance and optically by Kerr microscopy. The results show that the required current density for injection of domain walls is reduced by ∼20% with an applied electric field of +250 MV/m on the Hall cross structure.