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arXiv · 2303.05894

An Alternative Formulation of the Quantum Phase Estimation Using Projection-Based Tensor Decompositions

Marian Stengl
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Abstract

In this paper an alternative version of the quantum phase estimation is proposed, in which the Hadamard gates at the beginning are substituted by a quantum Fourier transform. This new circuit coincides with the original one, when the ancilla is initialized with $\ket{0}$. With the help of a projection-based tensor decomposition and closed-form expressions of its exponential, this new method can be interpreted as a multiplier coupled to the Hamiltonian of the corresponding target unitary operator. Based on this observation a recursive decomposition is derived.

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Marian Stengl. 2023-03-10. An Alternative Formulation of the Quantum Phase Estimation Using Projection-Based Tensor Decompositions. https://arxiv.org/abs/2303.05894

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