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Kronecker Product

^{First created in September 2018}

Code Section

# Initialisation

import sys
sys.path.append('../')
from qtol import *

# Kronecker multiplication with numpy

X = np.array([[0, 1], [1, 0]])
Z = np.array([[1, 0], [0, -1]])
S = np.array([[1, 0], [0, 1j]])
IZ = np.kron(np.eye(2), Z)
ZI = np.kron(Z, np.eye(2))
IX = np.kron(np.eye(2), X)
XI = np.kron(X, np.eye(2))

print(np.kron(Z,X))
print(np.kron(Z,S))

[[ 0  1  0  0]
 [ 1  0  0  0]
 [ 0  0  0 -1]
 [ 0  0 -1  0]]
[[ 1.+0.j  0.+0.j  0.+0.j  0.+0.j]
 [ 0.+0.j  0.+1.j  0.+0.j  0.+0.j]
 [ 0.+0.j  0.+0.j -1.+0.j -0.+0.j]
 [ 0.+0.j  0.+0.j -0.+0.j -0.-1.j]]