Research groups such as Hokkaido University have discovered a new phenomenon, the "reverse magnetic capacitance (iTMC) effect."This is the reverse phenomenon of the magnetic capacitance (TMC) effect, which has been widely known for a long time, and was discovered for the first time in the world.
The TMC effect is the capacitance (electrical capacitance) when the magnetization (direction of properties as a magnet) of the magnetic layers is parallel to each other in a junction in which a thin insulating layer is sandwiched between two magnetic layers (magnetic layers). A phenomenon in which the amount of electricity accumulated) becomes "large" and "small" when it is antiparallel.This time, the research group challenged the development of an unprecedented junction structure by combining iron and iron oxide, and the opposite phenomenon, that is, when the magnetization of the magnetic layer is parallel, the capacitance is "small", and when it is antiparallel. Succeeded in the manifestation of the "growth" phenomenon.
In addition, this mechanism has been elucidated by the charge storage theory incorporating quantum mechanics, and according to the theoretical calculation, the rate of change in capacitance (iTMC ratio) was obtained this time in the structure using iron nitride and cobalt iron boron alloy. It is said to be about 10 times larger than the value for iron.
If research on the iTMC effect is widely expanded with the results of this research as a starting point, the path to the birth of high-sensitivity, low-power consumption magnetic sensors and memories will be opened up along with the improvement of the iTMC ratio.In the future, it is expected to be applied to position detection sensor elements such as magnetic card readers and GPS, and non-volatile memory for mounting on personal computers and smartphones.
Paper information: [Scientific Reports]: Inverse Tunnel Magnetocapacitance in Fe / Al-oxide / Fe3O4