import numpy as np

## Constants here
e = 1.60217662e-19 # coulombs
h = 6.626e-34 # m^2*kg/s
hbar = h/(2*np.pi)
phi0 = h/(2*e)
G0 = e**2/h
eps0 = 8.854187817e-12 # F/m
m = 9.10938356e-31 # kg
mu0 = 4e-7*np.pi  # T*m/A
vF = 1e6  # m/s; Fermi velocity for graphene
