Research
① Research on charge-spin related materials and devices
A typical device is the magnetic tunnel junction. In our laboratory, we
research materials to dramatically improve the characteristics (tunnel
magnetoresistance effect). A magnetic tunnel junction is a laminated element
in which an insulating thin film is sandwiched between conductive thin
films that have magnetic properties. Each layer is on the order of a few
nanometers thick. When a voltage is applied to the conductors above and
below the insulator, a current flows due to the quantum mechanical tunneling
effect. It is also called a TMR element because it exhibits a tunnel magnetoresistive
effect (TMR effect) in which the electrical resistance of the element changes
depending on whether the magnetization (orientation of the magnetic poles)
of the two upper and lower magnets is parallel or antiparallel. This element
has been used in magnetic sensors and hard disk magnetic heads. Recently,
memory companies around the world are developing magnetoresistive random
access memory (MRAM). In addition, basic research on various artificial
intelligence hardware using this is being advanced worldwide. The tunnel
magnetoresistive effect is the most fundamental characteristic that determines
the performance of these various applied products.
Our laboratory pursues new and original magnetic electrode materials and
element insulation barrier materials led by PI Mizukami, and also conducts
unique research and development that incorporates computational science,
information science, and machine learning in collaboration with other groups.
This research is supported by CREST (JST) and Grant-in-Aid for Scientific
Research (S) (JSPS).
JST CREST : Overview and Results (Mizukami)
JSPSKAKENHI (S) : Overview and Results (Mizukami)
② Research on light-spin related materials and devices
We are conducting research to control the state and motion of magnetism
(spin) in nanomagnetic materials using laser light. We are also researching
basic physics and materials for high efficiency. It has been known for
a long time that there are various waves woven by magnetism (spin) in magnetic
materials. Research on low-power, high-speed von Neumann computers and
non-Von Neumann computers that use spin waves and spin states as carriers
for information storage, processing, and transmission is underway worldwide.
This is because the energy required for the motion of the spin is very
small, so there is the possibility of creating a new computer with high
energy efficiency.
In our laboratory, we have constructed an original spin measurement technique
using laser light led by PI Mizukami, and are proceeding with unique research
using pump-probe microscopes and terahertz wave radiation. We are also
researching memories and interfaces using light-spin and their materials.
In addition, under the leadership of Assistant Professor Iihama, we are
conducting research on computers using light-spin waves.
③ Research on quantum-spin related materials and devices
Research and development of various quantum technologies are progressing
worldwide. Research and development of quantum technology using spin defects
in diamond is one of them.
In our laboratory, we are researching on new technology comprising both
classic and quantum physiscs/materials, in particular spin defects in Diamond.