import sys
sys.path.insert(0, '..')
import numpy as np
import qutip as qt
import src
from src import (utils, paulialg, stabilizer, circuit)

1.6. Link to QuTip Library

Pauli operators can be easily converted to the Qobj in qutip library

• Pauli.to_qupit()

• PauliList.to_qutip()

• PauliMonomial.to_qutip()

• PauliPolynomial.to_qutip()

paulialg.pauli('XY').to_qutip()

\[\begin{split}Quantum object: dims = [[2, 2], [2, 2]], shape = (4, 4), type = oper, isherm = True\begin{equation*}\left(\begin{array}{*{11}c}0.0 & 0.0 & 0.0 & -1.0j\\0.0 & 0.0 & 1.0j & 0.0\\0.0 & -1.0j & 0.0 & 0.0\\1.0j & 0.0 & 0.0 & 0.0\\\end{array}\right)\end{equation*}\end{split}\]

paulialg.paulis('XY','ZZ').to_qutip()

[Quantum object: dims = [[2, 2], [2, 2]], shape = (4, 4), type = oper, isherm = True
 Qobj data =
 [[0.+0.j 0.+0.j 0.+0.j 0.-1.j]
  [0.+0.j 0.+0.j 0.+1.j 0.+0.j]
  [0.+0.j 0.-1.j 0.+0.j 0.+0.j]
  [0.+1.j 0.+0.j 0.+0.j 0.+0.j]],
 Quantum object: dims = [[2, 2], [2, 2]], shape = (4, 4), type = oper, isherm = True
 Qobj data =
 [[ 1.  0.  0.  0.]
  [ 0. -1.  0.  0.]
  [ 0.  0. -1.  0.]
  [ 0.  0.  0.  1.]]]

((2+3j)*paulialg.pauli('XY')).to_qutip()

\[\begin{split}Quantum object: dims = [[2, 2], [2, 2]], shape = (4, 4), type = oper, isherm = False\begin{equation*}\left(\begin{array}{*{11}c}0.0 & 0.0 & 0.0 & (3.0-2.0j)\\0.0 & 0.0 & (-3.0+2.0j) & 0.0\\0.0 & (3.0-2.0j) & 0.0 & 0.0\\(-3.0+2.0j) & 0.0 & 0.0 & 0.0\\\end{array}\right)\end{equation*}\end{split}\]

((2+3j)*paulialg.pauli('XY')+(1.5)*paulialg.pauli('ZZ')).to_qutip()

\[\begin{split}Quantum object: dims = [[2, 2], [2, 2]], shape = (4, 4), type = oper, isherm = False\begin{equation*}\left(\begin{array}{*{11}c}1.500 & 0.0 & 0.0 & (3.0-2.0j)\\0.0 & -1.500 & (-3.0+2.0j) & 0.0\\0.0 & (3.0-2.0j) & -1.500 & 0.0\\(-3.0+2.0j) & 0.0 & 0.0 & 1.500\\\end{array}\right)\end{equation*}\end{split}\]