The application landscape for optimal control of digital and analog Rydberg quantum computers

Arrays of neutral atoms controlled by laser beams and optical tweezers represent a scalable quantum technology with flexible connectivity. They offer both a digital mode, where qubit evolution is governed by quantum gates, and an analog counterpart, where control is achieved by manipulating the effective Rydberg Hamiltonian. Here, we apply our quantum optimal control (QOC) suite to address a range of tasks in the strontium-88 Rydberg device developed within the QRydDemo project; the qubit is encoded into two fine-structure states, and the Rydberg state is used only for entangling operations. Taking into account finite temperature and a finite rise time for the laser pulses, we employ open-loop QOC to optimize the shuffling of atoms within the array, to implement an optimal pulse sequence for a CZ gate, and to optimize complex algorithms. Our CZ gate optimization shortens the time spent in the Rydberg state by 10% compared to the state-of-the-art protocol, thus allowing 99.9% fidelity when considering fundamental error sources.