We propose an entanglement protocol where ions illuminated by optical tweezers serve as control qubits. We experimentally demonstrate this proposal with a controlled M\olmer-S\orensen operation on a three-ion chain, analogous to the canonical Toffoli gate. Our demonstration features cases in which the control qubit was in one of its logical basis states, and not in their superposition, due to dephasing by tweezer beam intensity fluctuations. Finally, we discuss how our protocol generalizes to a broad class of unitary operations and larger qubit systems, enabling a single-pulse implementation of n-controlled unitaries.
@article{arxiv.2506.08565,
title = {Optical tweezer-controlled entanglement gates with trapped ion qubits},
author = {David Schwerdt and Lee Peleg and Gal Dekel and Lekshmi Rajagopal and Oz Matoki and Avram Gross and Yotam Shapira and Nitzan Akerman and Roee Ozeri},
journal= {arXiv preprint arXiv:2506.08565},
year = {2025}
}