A quantum while loop for amplitude amplification
Year: 2020
Type: preprint
Abstract: Grover's algorithm searches an unstructured database of $N$ entries, finding a marked element in time $\mathcal{O}(\sqrt{N})$. The algorithm was later generalised to amplitude amplification. The original algorithm succeeds with probability close to one and needs to run for a number of iterations chosen ahead of time. We discuss an implementation of amplitude amplification that, instead, runs for a number of iterations unspecified a priori and only halts on success. We prove that this approach maintains the quadratic speed-up of the original quantum algorithm. The key component is a feedback loop controlled by a weak measurement that allows limited monitoring of the evolution of the quantum state.
Source: arXiv (Cornell University)
Authors: Pablo Andrés-Martínez, Chris Heunen
Language: English
Subfield: Artificial Intelligence
Field: Computer Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3087414439