{"cells":[{"cell_type":"text","text":"<h1>Quantum Fourier Transform</h1>"},{"code":"%load_ext sympy_printing","cell_type":"code","prompt_number":1},{"code":"from sympy import sqrt, symbols, Rational\nfrom sympy import expand, Eq, Symbol, simplify, exp, sin\nfrom sympy.physics.quantum import *\nfrom sympy.physics.quantum.qubit import *\nfrom sympy.physics.quantum.gate import *\nfrom sympy.physics.quantum.grover import *\nfrom sympy.physics.quantum.qft import QFT, IQFT, Fourier\nfrom sympy.physics.quantum.circuitplot import circuit_plot","cell_type":"code","prompt_number":2},{"cell_type":"text","text":"<h2>QFT Gate and Circuit</h2>"},{"cell_type":"text","text":"Build a 3 qubit QFT and decompose it into primitive gates."},{"code":"fourier = QFT(0,3).decompose(); fourier\n","cell_type":"code","prompt_number":3},{"code":"circuit_plot(fourier, nqubits=3)","cell_type":"code","prompt_number":4},{"cell_type":"text","text":"The QFT circuit can be represented in various symbolic forms."},{"code":"m = represent(fourier, nqubits=3)","cell_type":"code","prompt_number":5},{"code":"m","cell_type":"code","prompt_number":6},{"code":"represent(Fourier(0,3), nqubits=3)*4/sqrt(2)\n","cell_type":"code","prompt_number":7},{"cell_type":"text","text":"<h2>QFT in Action</h2>"},{"cell_type":"text","text":"Build a 3 qubit state to take the QFT of."},{"code":"state = (Qubit('000') + Qubit('010') + Qubit('100') + Qubit('110'))/sqrt(4); state\n","cell_type":"code","prompt_number":8},{"cell_type":"text","text":"Perform the QFT."},{"code":"qapply(fourier*state)\n","cell_type":"code","prompt_number":9},{"code":"%notebook save qft.ipynb","cell_type":"code","prompt_number":23},{"code":"%notebook load qerror.ipynb","cell_type":"code","prompt_number":207}]}