Electric-field control of ferromagnetism in GaSb/Mn digital alloys

We have investigated the dependence of ferromagnetism in GaSb/Mn digital alloys on applied electric bias perpendicular to the digital layers. The remanent Hall resistance determined from hysteresis loops in RHall vs. magnetic field was used as a measure of the ferromagnetism present in two samples at temperatures between 5 and View the MathML source. With applied gate bias, the remanent Hall resistance measured in gated Hall bars was found to change systematically with applied bias. The changes agree qualitatively with changes in carrier concentration determined from the sheet resistance vs. bias. Ferromagnetism in these samples can be turned on and off with applied bias near the Curie temperature (as high as View the MathML source in one sample).