868 B
868 B
Another well known quantum algorithm for searching.
Takes a function f : \{0,1\}^n \rightarrow \{0,1\} where f(x) = 1 for exactly one x.
The goal is to find x.
New gates: V_f and FLIP$_*$
\ket{*} denotes the superposition over al classical possibilities.
Oracle V_f
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We use the Unitary U_f as previously defined to construct V_f
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FLIP$_*$
We first need FLIP$_0$ defined as follows:
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This is implemented via this circuit:
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Z is a Pauli matrix and the empty circles denote negative control wires.
So Z is only applied if all other wires are \ket{0}
Now we define the unitary FLIP$_*$:
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