Non-unitary extension of Grover's search algorithm
Abstract
We have developed a non-unitary extension of Grover's search algorithm by changing the hidden geometry of Hilbert space carried by diffusion operator. Our algorithm finds the solution for search problem by performing a unique bigger rotation rather than small rotations in order polynomial times in the size of search space. We analyze the complexity of implementing the non-unitary operation and we observed that the price paid by performing this rotation is due the normalization. In Kraus operator approach we need repetition of the algorithm to have a chance of measuring a solution in a post-selection, this is no better than the classical solution. However, the quantum singular value transform in addition with block encoding and Chebyshev polynomial approximation, we got complexity and reach the Grover's bound with an extra resource of one single qubit, compared with the standard Grover's algorithm.
Keywords
Cite
@article{arxiv.2604.23382,
title = {Non-unitary extension of Grover's search algorithm},
author = {V. N. A. Lula-Rocha and M. A. S. Trindade},
journal= {arXiv preprint arXiv:2604.23382},
year = {2026}
}