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arXiv · 2202.02671

Stable factorization for phase factors of quantum signal processing

Lexing Ying
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Abstract

This paper proposes a new factorization algorithm for computing the phase factors of quantum signal processing. The proposed algorithm avoids root finding of high degree polynomials by using a key step of Prony's method and is numerically stable in the double precision arithmetics. Experimental results are reported for Hamiltonian simulation, eigenstate filtering, matrix inversion, and Fermi-Dirac operator.

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Lexing Ying. 2022-02-06. Stable factorization for phase factors of quantum signal processing. https://doi.org/10.22331/q-2022-10-20-842

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