Electric field modifications on the coercive force for electrochemical etched Co/Pt(111) films

The electrochemical etching process for Co/Pt(111) removes the surface atoms ended with a smooth surface and less surface defects due to the appearance of chloride anions. During the electrochemical etching process for Co/Pt(111), the squareness of the hysteresis loop remains nearly unity. The coercive force of Co/Pt(111) after electrochemical etching treatments is slightly enhanced while the electric field control of the coercive force with larger responses is demonstrated. The potential range for magnetic measurements is chosen between − 400 and − 600 mV to avoid the influences of the possible deposition/etching of the films. Within this potential window, the electric field control of the magnetic properties is manageable. Variations of the coercive force between 0.31 and 0.38 kOe are reproducible for electrochemical etched Co/Pt(111) under conditions of repeatedly electric potential at − 500 and − 400 mV. The easiness for operation, thickness control of magnetic films, and electric field modification of coercive force in an electrolyte condition show great advantages for further applications in spintronics.