Shortcut-to-Adiabatic Controlled-Phase Gate in Rydberg Atoms

A shortcut-to-adiabatic protocol for the realization of a fast and high-fidelity controlled-phase gate in Rydberg atoms is developed. The adiabatic state transfer, driven in the high-blockade limit, is sped up by compensating nonadiabatic transitions via oscillating fields that mimic a counterdiabatic Hamiltonian. High fidelities are obtained in wide parameter regions. The implementation of the bare effective counterdiabatic field, without original adiabatic pulses, enables to bypass gate errors produced by the accumulation of blockade-dependent dynamical phases, making the protocol efficient also at low blockade values. As an application toward quantum algorithms, how the fidelity of the gate impacts the efficiency of a minimal quantum-error correction circuit is analyzed.Quantum gates are the backbone of digital quantum computing. A shortcut-to-adiabatic protocol is presented for the realization of controlled-phase gate in Rydberg atoms. The adiabatic state transfer for the gate is accelerated by compensating nonadiabatic transitions via oscillating fields. High fidelities and fast operation times are obtained, and an application to a minimal quantum-error correction circuit is analyzed. image