Capacitors, electronic components that store and quickly release a charge, play an important role in many types of electrical circuits. They’ll play an equally important role in next-generation spintronic devices, which take advantage of not only electron charge but also spin — the tiny magnetic moment of each electron.
Two years ago, an international team of researchers showed that by manipulating electron spin at a quantum magnetic tunneling junction — a nanoscale sandwich made of two metal electrodes with an insulator in the middle — they could induce a large increase in the junction’s capacitance.
Now, that same research team has flipped the script on the phenomenon, known as magnetocapacitance. In a paper published in the journal Scientific Reports, they show that by using different materials to build a quantum tunneling junction, they were able to alter capacitance by manipulating spins in the opposite way from “normal” magnetocapacitance. This inverse effect, the researchers say, adds one more potentially useful phenomenon to the spintronics toolkit.