Pseudo-gauge Fields in Dirac and Weyl Materials

Understand

Electrons in low-temperature solids are governed by the non-relativistic Schr$\ddot{o}$dinger equation, since the electron velocities are much slower than the speed of light.

• Remarkably, the low-energy quasi-particles given by electrons in various materials can behave as relativistic Dirac/Weyl fermions that obey the relativistic Dirac/Weyl equation.
• These materials are called "Dirac/Weyl materials", which provide a tunable platform to test relativistic quantum phenomena in table-top experiments.
• More interestingly, different types of physical fields in these Weyl/Dirac materials, such as magnetic fluctuations, lattice vibration, strain, and material inhomogeneity, can couple to the "relativistic" quasi-particles in a similar way as the $U(1)$ gauge coupling.