Jie Ning

In the relentless pursuit of quantum computational advantage, we present a significant advancement with the development of Zuchongzhi 3.0. This superconducting quantum computer prototype, comprising 105 qubits, achieves high operational fidelities, with single-qubit gates, two-qubit gates, and readout fidelity at 99.90%, 99.62%, and 99.13%, respectively. Our experiments with an 83-qubit, 32-cycle random circuit sampling on the Zuchongzhi 3.0 highlight its superior performance, achieving 1×10^{6} samples in just a few hundred seconds. This task is estimated to be infeasible on the most powerful classical supercomputers, Frontier, which would require approximately 5.9×10^{9} yr to replicate the task. This leap in processing power places the classical simulation cost 6 orders of magnitude beyond Google's SYC-67 and SYC-70 experiments [Morvan et al., Nature 634, 328 (2024)10.1038/s41586-024-07998-6], firmly establishing a new benchmark in quantum computational advantage. Our work not only advances the frontiers of quantum computing but also lays the groundwork for a new era where quantum processors play an essential role in tackling sophisticated real-world challenges.

In a practical system of commerce sites, we not only need to focus on their own functional requirements, but also need to consider many other security requirements. Security is a very important aspect. Access control occupies a vital role in a website system. To solve the problem of access control is to solve a majority of the security problem. The role-based access control model separated users and permission with logically, meanwhile it reduces the complexity of management, and reduces administrative overhead and management complexity. The role-based access control model will play an important role in the increasing size of business information management system. We can use the role-based access control model to solve the problem of access control, and put it into the information system.

Accurate characterization of carrier mobility in scaled CMOS at cryogenic temperatures is essential for applications such as quantum computing. This article presents a comprehensive study of effective carrier mobility in a 55-nm bulk CMOS technology at 4 K. Using a physics-based extraction technique, we decompose the inverse mobility into its constituent weak-field (Coulomb) and strong-field (surface roughness) scattering components. The characterization across various device geometries and threshold voltage options reveals that mobility degradation at 4 K is primarily governed by the weak-field component. A significant finding is the asymmetric width dependence, where PMOS mobility is strongly enhanced in narrow channels due to mechanical stress, while NMOS mobility remains largely unaffected. An empirical model for the key scattering parameters is developed and validated against a verification set of experimental data, demonstrating excellent predictive accuracy for drain current. The results provide critical physical insights and a direct pathway for developing accurate cryogenic compact models, with important circuit implications for device selection and layout optimization.