Function quest_sys::controlledPhaseFlip

pub unsafe extern "C" fn controlledPhaseFlip(
    qureg: Qureg,
    idQubit1: c_int,
    idQubit2: c_int
)

Apply the (two-qubit) controlled phase flip gate, also known as the controlled pauliZ gate. For each state, if both input qubits have value one, multiply the amplitude of that state by -1. This applies the two-qubit unitary: \f[ \begin{pmatrix} 1 \ & 1 \
& & 1 \ & & & -1 \end{pmatrix} \f] with circuit diagram: \f[ \begin{tikzpicture}[scale=.5] \node[draw=none] at (-3.5, 2) {idQubit1}; \node[draw=none] at (-3.5, 0) {idQubit2};

\draw (-2, 2) – (2, 2); \draw[fill=black] (0, 2) circle (.2); \draw (0, 2) – (0, 0);

\draw (-2,0) – (2, 0); \draw[fill=black] (0, 0) circle (.2); \end{tikzpicture} \f]

@see

• pauliZ()
• phaseShift()
• multiControlledPhaseFlip()

@ingroup unitary @param[in,out] qureg object representing the set of all qubits @param[in] idQubit1, idQubit2 qubits to operate upon @throws invalidQuESTInputError()

• if \p idQubit1 or \p idQubit2 are outside [0, \p qureg.numQubitsRepresented)
• if \p idQubit1 and \p idQubit2 are equal @author Tyson Jones