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Questions tagged [amplitude-amplification]

For questions about the amplitude-amplitude algorithm. Do NOT use for general Grover's algorithm related question. Amplitude amplification is a technique in quantum computing which generalizes the idea behind Grover's search algorithm and gives rise to a family of quantum algorithms. It was discovered by Gilles Brassard and Peter Høyer in 1997 and independently rediscovered by Lov Grover in 1998. (Wikipedia)

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Amplitude suppression

On contrary to amplitude amplification, can I do some reflection such that my marked states' probability will vanish (ideally become zero but if there are small residuals also acceptable)? In order to preserve the normalization condition, all the…
Sam
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Amplifying entangled qubits

Suppose I have a three-qubit entangled state of the following form: $$ |00\rangle|\psi_1\rangle + |01\rangle|\psi_2\rangle + |10\rangle|\psi_3\rangle + |11\rangle|\psi_4\rangle $$ I refer to the first two qubits as address qubits. The third qubit…
epelaez
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How to understand picking a random subcube in the Aaronson/Ambainis spatial search algorithm?

I am referring to the Quantum Search of Spatial Regions paper. I must confess that the paper itself is a bit heavy for my level of mathematical fluency. Trying to understand it nevertheless and having some background in QC, I have stumbled upon the…
Stanislaw
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Can one obliviously reflect about the *initial* state in fixed-point amplitude amplification?

It is normal to extend fixed-point amplitude amplification to an oblivious version, i.e., $1 - (1-e^{i \beta})|t\rangle \langle t | \rightarrow 1 - (1-e^{i \beta}) 1 \otimes |0\rangle \langle 0|$, and one uses an additional ancilla to apply a phase…
kηives
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Amplitude amplification for known state but unknown amplitude

I have a circuit that prepares a state $|s\rangle$ which is a superposition of the basis states $$\sum_{x=0}^{2^{n-1}}\alpha_x|x\rangle$$ with amplitude $\alpha_x$ for a circuit of $n$ qubits. Particularly, the solution to the problem I'm looking is…
César Leonardo Clemente López
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