version 0.0.51

Tutorial/calculate_Chern_number_and_Wilson_loop.py

@@ -1,24 +0,0 @@
-import guan
-import numpy as np
-from math import *
-
-# calculate Chern number
-def hamiltonian_function(kx, ky):  # one QAH model with chern number 2
-    t1 = 1.0
-    t2 = 1.0
-    t3 = 0.5
-    m = -1.0
-    hamiltonian = np.zeros((2, 2), dtype=complex)
-    hamiltonian[0, 1] = 2*t1*cos(kx)-1j*2*t1*cos(ky)
-    hamiltonian[1, 0] = 2*t1*cos(kx)+1j*2*t1*cos(ky)
-    hamiltonian[0, 0] = m+2*t3*sin(kx)+2*t3*sin(ky)+2*t2*cos(kx+ky)
-    hamiltonian[1, 1] = -(m+2*t3*sin(kx)+2*t3*sin(ky)+2*t2*cos(kx+ky))
-    return hamiltonian
-chern_number = guan.calculate_chern_number_for_square_lattice(hamiltonian_function, precision=100)
-print('Chern number=', chern_number)
-
-# calculate Wilson loop
-wilson_loop_array = guan.calculate_wilson_loop(guan.hamiltonian_of_ssh_model)
-print('Wilson loop =', wilson_loop_array)
-p = np.log(wilson_loop_array)/2/pi/1j
-print('p =', p, '\n')