Question

A famous continuum model of Dirac semimetal is essentially two copies of the following Hamiltonian (up to some chirality reversal)

h=(M(k)Ak−Ak+−M(k))
with k±=kx±iky
and M(k)=M0−M1k2z−M2(k2x+k2y)
. For instance, this is found on page 8 of this seminal work. There, the fitting parameter values of A,M0,1,2
are given for a realistic Dirac semimetal and widely used as a reference.

Actually, h
is also a Weyl semimetal model on its own. So are there any similar parameter values given for some typical Weyl materials?
A) No, parameter values for typical Weyl materials are not available as they significantly differ from Dirac semimetals.
B) Yes, parameter values for typical Weyl materials exist and can be found in various experimental and theoretical studies.
C) Partially, there are few parameter values available for certain Weyl materials, but not as extensively as for Dirac semimetals.
D) No, there is a lack of parameter values for typical Weyl materials due to the complexity of their electronic structure.

Answer 1

Parameter values for typical Weyl materials are indeed available and can be obtained through experimental and theoretical research. Weyl semimetals differ from Dirac semimetals due to their distinct symmetries but share certain electronic properties that can also be characterized by specific parameters.

Step-by-step explanation:

The question revolves around the continuum model of Dirac semimetals and whether similar parameter values to those of Dirac semimetals can be found for Weyl semimetals. In the context of the provided scientific descriptions, it is clear that there are indeed parameter values for Weyl materials.

These values can be derived from experimental and theoretical studies. Weyl semimetals differ from Dirac semimetals by lacking inversion symmetry or time-reversal symmetry, but they also can be characterized by parameters related to their electronic structure.

Our understanding of atoms, quantum mechanics, and the behavior of electrons—whether they're modeled as free particles or as carriers in a lattice—provides a foundation for differentiating between fermions and bosons, addressing the concepts of spin, and the Pauli exclusion principle.

These principles underlie the differences between Dirac and Weyl semimetals. Details about spectral lines, intrinsic spin, and space quantization all hint that the world of solid-state physics has complexities that often require tailored parameters for each type of material, including Weyl semimetals.