The electronic devices used in present-day computers, from CPU to the memory and storage devices, have the fundamental issue of large power consumption. For example, a volatile memory such as a DRAM or SRAM requires a continuous supply of electric power. On the other hand, in the case of a non-volatile memory, the recorded data will not disappear even when the power is switched OFF. This non-volatility enables to cut off the standby current. While the device is operating, however, even a non-volatile memory requires an electronic current to write data, and electric power is consumed.

This program, which utilizes the most advanced spintronics, which is based on non-volatility, is aimed at the development of a spintronic memory with ultra-low power consumption. Spintronics is a field of science and technology in which not only the electronic of an electron but also the electronic spin (rotation of the electron), causing the basis of a magnet, is controlled. Spintronics can be applied to engineering fields such as data recording and transmission. By using spintronics, data is maintained even when the electric power is interrupted, and the electric power only need druring reading or writing data. Also, the electric power is not required for the entire integrated circuit, but only for the required part, that resets in drastic reduction of power consumption.

In this program, the innovative integrated circuits utilizing the spintronics devices is developed. The revolutionary feature of this program is that the voltage or electric-field control is applied to the developing devices, instead of the usually used current-control. The voltage-controlled spintronics devices need almost no current, thus drastically suppress heat generation. Ultimately, we are aiming to realize the data storage even under the power OFF, and to reduce the active power consumption to 1/100 of that of a conventional device.

The background of this R&D “from current-control to voltage-control” resembles the revolution of present-day electronics from a vacuum tube to a current-controlled bipolar transistor to a voltage-controlled field effect transistor (FET) utilizing only the electron charges. Even in the field of spintronics, if we realize the disruptive innovation in the spintronics technology from the current-controlled device to the voltage-controlled-device which is considered to be impossible so far, the big game-change can ce caused.