Quantum walks as mathematical foundation for quantum gates
Abstract
It is demonstrated that in gate-based quantum computing architectures quantum walk is a natural mathematical description of quantum gates. It originates from field-matter interaction driving the system, but is not attached to specific qubit designs and can be formulated for very general field-matter interactions. It is shown that, most generally, gates are described by a set of coined quantum walks. Rotating wave and resonant approximations for field-matter interaction simplify the walks, factorizing the coin, and leading to pure continuous time quantum walk description. The walks reside on a graph formed by the Hilbert space of all involved qubits and auxiliary states, if present. Physical interactions between different parts of the system necessary to propagate entanglement through such graph -- quantum network -- enter via reduction of symmetries in graph edges. Description for several single- and two-qubit gates are given as examples.
Cite
@article{arxiv.1906.11701,
title = {Quantum walks as mathematical foundation for quantum gates},
author = {Dmitry Solenov},
journal= {arXiv preprint arXiv:1906.11701},
year = {2020}
}
Comments
33 pages, 5 figures