"""Module to calculate the dark-matter screening."""
import numpy as np
[docs]def peskin_schroeder_constant(bandgap=None, fermi_velocities=[], epsilon=[]):
"""
Provide Peskin Scroeder constant for a material.
Just proportionality constant. Doesn't take into account
g and Lambda.
Args:
bandgap: benadgap in eV.
fermi_velocities: vx, vy, vz
epslion: eigenvalues of epsilon tensor
Return:
1/(epsion*vF)
"""
return 1 / (np.array(fermi_velocities) * np.array(epsilon))
"""
if __name__ == "__main__":
epsilon = [187.5, 9.8, 90.9]
fermi_velocities = [0.0029, 0.0050, 0.0021]
print(
peskin_schroeder_constant(
bandgap=0.035, fermi_velocities=fermi_velocities, epsilon=epsilon
)
)
"""