Single-flux-quantum-based qubit control with tunable driving strength

Single-flux-quantum(SFQ)circuits have great potential in building cryogenic quantum-classical interfaces for scaling up superconducting quantum processors.SFQ-based quantum gates have been designed and realized.However,current control schemes are difficult to tune the driving strength to qubits,which restricts the gate length and usually induces leakage to unwanted levels.In this study,we design the scheme and corresponding pulse generator circuit to continuously adjust the driving strength by coupling SFQ pulses with variable intervals.This scheme not only provides a way to adjust the SFQ-based gate length,but also proposes the possibility to tune the driving strength envelope.Simulations show that our scheme can suppress leakage to unwanted levels and reduce the error of SFQ-based Clifford gates by more than an order of magnitude.

抗结核新药德拉马尼作用机理和化学合成的研究进展

结核分枝杆菌感染导致的结核病仍然是全球重大公共卫生威胁。耐多药结核分枝杆菌感染所致的耐多药结核病则是2035年实现终结结核病的主要障碍之一。德拉马尼是近50年来成功研发并上市的抗结核新药之一。德拉马尼主要依据抑制枝菌酸合成的酶筛选获得,但是,其具体靶标仍然有待研究。本文综述前药德拉马尼的激活途径和基因、转录组效应、作用靶标以及化学合成,为进一步精准确定其药靶提供基础。

Fabrication and characterization of all-Nb lumped-element Josephson parametric amplifiers

Josephson parametric amplifiers (JPAs) with nearly quantum-limited noise performance have become indispensable devices for the measurements of superconducting quantum information. We have developed an all-Nb lumped-element flux-driven JPA operating in the three-wave mixing mode. Our Nb-based JPA comprises Nb/Al-AlOx/Nb Josephson junctions, a parallel-plate capacitor with SiO2 dielectric sandwiched between two Nb layers, a bottom coplanar waveguides layer, and a top Nb wiring layer. We experimentally demonstrate a 20 dB gain over a 190 MHz bandwidth, a mean 1 dB compression of -123 dBm, and near quantum-limited noise performance. This fabrication process can be further used to design impedance transformed parametric amplifiers for multiple-qubit readout.

基于核心素养的生物学高考试题考点分析及启示——以新型冠状病毒感染情境为例

解析了生物学高考试题如何以新型冠状病毒感染为知识载体发展学生的核心素养,以期为中学生物学教师结合新型冠状病毒感染开展教育教学活动提供参考。

基于前馈控制优化和PID变参数改造的热电AGC优化控制研究

在电力行业不断改革的背景下,火力发电厂面临着提供既经济又优质的电力的双重挑战。从供电端来看,用户期望获得稳定且质量上乘的电力供应,以满足其用电需求及其变化。这就要求电网能够提供符合标准的电压和频率,以确保电能的质量。然而,电网本身并不产生电能,它主要负责电能的传输和分配。因此,电能的质量最终依赖于发电端。为了确保发电端能够向电网提供高质量的电能,优化自动发电控制系统(AGC)是一个有效的策略。AGC控制系统的优化不仅能提高发电效率,降低成本,还能确保电能的稳定性和可靠性,满足用户对电力质量的高标准要求。本研究以中卫电厂的火电机组为例,开展针对锅炉主控静态前馈控制的优化改造,同时执行针对锅炉主控PID变参数和中间点过热度PID输出上下限的改造。