Capacitors are electronic elements which store and quickly release a charge. These play a significant role in diverse electrical circuits.
Two years ago, a team of international scientists showed that by manipulating electron spin at a nanoscale sandwich consisting of an insulator flanked by two metal electrodes, a large increase in the junction's capacitance could be induced.
Currently, that same research team has reversed the existing positions on the magnetocapacitance phenomenon. They have showed that by using varied materials (iron and iron oxide) in a quantum tunneling junction, capacitance can be altered by manipulating spins in the opposite way from "normal" magnetocapacitance. This is observed because the electrical properties of the two elements are each other’s mirror images.
They believe that this inverse effect adds another possibly useful phenomenon to the spintronics toolkit.
"It gives us more parameter space to design devices. Sometimes normal capacitance might be better; sometimes the inverse might be better, depending on the application. This gives us a bit more flexibility" stated one of the co-authors.
These magnetocapacitors could have application in making magnetic sensors for a variety of spintronic devices, like next-generation random access memory chips and computer hard drives.