Discovery of Weyl semimetal state violating Lorentz invariance in MoTe2

Understand

A new type of Weyl semimetal state, in which the energy values of Weyl nodes are not the local extrema, has been theoretically proposed recently, namely type II Weyl semimetal.

• Distinguished from type I semimetal (e.g.
• TaAs), the Fermi surfaces in a type II Weyl semimetal consist of a pair of electron and hole pockets touching at the Weyl node.
• In addition, Weyl fermions in type II Weyl semimetals violate Lorentz invariance.