A neutral-atom system serves as a promising platform for realizing gate-based quantum computing because of its capability to trap and control several atomic qubits in different geometries and the ability to perform strong, long-range interactions between qubits; however, the two-qubit entangling gate fidelity lags behind competing platforms such as superconducting systems and trapped ions. The aim of our work is to design a fast, robust, high-fidelity controlled-
Z (cz) gate, based on the Rydberg-blockade mechanism, for neutral atoms. We propose a gate procedure that relies on simultaneous and transitionless quantum driving of a pair of atoms using broadband lasers. By simulating a system of two interacting cesium atoms, including spontaneous emission from excited levels and parameter fluctuations, we yield a Rydberg-blockade cz gate with fidelity 0.9985 over an operation time of $0.12\phantom{\rule{3.33333pt}{0ex}}\mathrm{\textmu{}s}$. Our gate procedure delivers cz gates that are superior than the state-of-the-art experimental cz gate and the simulated cz gates based on adiabatic driving of atoms. Our results show that our gate procedure carries significant potential for achieving scalable quantum computing using neutral atoms.
Abstract Quantum logic gates are the fundamental operational units in quantum computing. The SWAP gate, as an important two‐qubit logic gate, has long been the focus of scholars for seeking to achieve high‐fidelity implementations. This study proposes a scheme for realizing a SWAP gate using Rydberg atoms. The scheme ingeniously utilizes the interactions between Rydberg atoms to construct the model and combines the “transitionless quantum driving” algorithm to design the control laser. Numerical simulations show that this scheme not only achieves a high‐fidelity SWAP gate but also robust against experimental imperfections such as atomic spontaneous emission. At last, this scheme is extended to realize CSWAP gate.