Deterministic linear-optical computing with symmetry-based qubits
Quantum Physics
2026-04-09 v1
Abstract
A particular type of linear optical multiport, the Grover four-port, has previously been shown to couple the spatial symmetry of a photon to its direction of travel. It is shown here that use of a nonstandard choice of qubit, based on symmetry, allows Grover four ports to act as compact, low-resource deterministic linear optical controlledNOTgates, with no post-selection or ancilla measurements required. This approach allows programmable devices, made from Grover multiports in combination with other standard optical components, that can implement multiple different one-, two-, and three-qubit gates, including the Fredkin and Toffoli gates.
Cite
@article{arxiv.2604.06584,
title = {Deterministic linear-optical computing with symmetry-based qubits},
author = {David S. Simon and Christopher R. Schwarze and Anthony D. Manni and Abdoulaye Ndao and Alexander V. Sergienko},
journal= {arXiv preprint arXiv:2604.06584},
year = {2026}
}