A research group led by Professor Satoshi Nakatsuji of the University of Tokyo, in collaboration with RIKEN, discovered Weil particles experimentally inside a magnetic material (manganese tristin Mn3Sn) for the first time in the world.For the first time in the world, we have discovered a new magnetic material, "Weil magnetic material," which is different from conventional ferromagnets and antiferromagnetic materials.
"Weil particles" are particles with zero mass, and the existence of mass was confirmed in 1998 for the candidate neutrino.However, in 2015, non-magnetic Weil particles were discovered in a solid non-magnetic substance (tantalum arsenate).On the other hand, since the magnetic Weil particles, which were initially predicted to exist, can be controlled by an external magnetic field, they are indispensable for device applications, and fierce search competition has been developed all over the world.
The Weil particles discovered in this research are "magnetic Weil particles" created by the magnetism of matter, which has a completely different expression mechanism from the Weyl particles found in conventional non-magnetic materials.This discovery means that Mn3Sn is a new magnetic material "Weil magnetic material" that can freely manipulate magnetic Weil particles with zero mass under the control of an external magnetic field.By simply applying a small magnetic field to a Weil magnetic material, it becomes possible to control the huge magnetic field (virtual magnetic field felt by conduction electrons in a substance) created by magnetic Weil particles.
This Weil magnetic material can exhibit unique material properties with new quantum functions at room temperature.It is possible to generate a huge "Hall voltage" without a magnetic field, or to induce a current in a solid in the same direction as in a magnetic field.It was also found that the huge magnetic field created by magnetic Weil particles plays an important role in the huge magnetic transport phenomena and thermoelectric effects observed in this material.
In the future, it is expected that the development of innovative next-generation devices with new functions will progress by utilizing the quantum mechanical properties of Weil particles.
Paper information:[Nature Materials] Evidence for Magnetic Weyl Fermions in a Correlated Metal
