基于本征约瑟夫森结阵列的可调超导滤波器及非线性机制研究

项目名称： 基于本征约瑟夫森结阵列的可调超导滤波器及非线性机制研究

项目编号： No.61471208

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 无线电电子学、电信技术

项目作者： 张旭

作者单位： 南开大学

项目金额： 70万元

中文摘要： 超导可调滤波器凭借低损耗、高选择性、高灵敏度和小体积等优点在移动通信、卫星通信以及军事电子设备等领域应用前景。本项目将采用理论分析、数值仿真和实验相结合的方法，研究基于本征约瑟夫森结阵列的可调超导滤波器及其非线性机制。相位锁定特性是实现约瑟夫森结阵列等效电感可调的核心问题，而将可调电感嵌入耦合型超导滤波器就可以实现滤波器的中心频率、带宽和陡峭度独立可调节。本项目将研究中心频率1.9GHz，带宽20MHz，可调范围20%的10阶超导滤波器，并探索调谐过程中非线性失真产生的原因，给出抑制失真的参数范围。 项目还将研究提高滤波器功率承载能力的方法，利用纳米颗粒修饰衬底表面和直接引入纳米颗粒制备多层结构超导薄膜两种方法，诱导薄膜内部出现晶界缺陷，提高薄膜的磁通钉扎强度和临界电流密度，最终制备出高功率承载能力的可调超导滤波器。

中文关键词： 超导滤波器；超导薄膜；超导材料制备；特性测试

英文摘要： Due to the low insertion loss, high selectivity, high sensitivity and small size, tunable superconducting filters have broad application prospects in many areas such as mobile communications, satellite communications, and military weapons.Tunable superconducting filter based on intrinsic Josephson junction arrays and its nonlinear characteristic would be studied in this project by using theoretical analysis, numerical simulation and experimentation. Phase-locking of intrinsic Josephson junction arrays is the key problem to realize tunable equivalent inductance and to correct the centre frequency, bandwidth and skirt characteristics of superconducting filter independently. We would give phase-locking regions of different parameters and develop 10-pole tunable filter with central frequency of 1.9GHz, bandwidth of 20MHz and tuning range of 20%. Symmetric distortions and asymmetric distortions are also investigated theoretically and experimentally. Furthermore we perform exploratory research on nonlinear mechanism in tunable superconducting filter. The project will also study nano-particle additions in superconducing films and introducing buffer layer to get multilayer films to generate the pinning centers and improve the flux pinning strength and critical current density. Finally,a noveltunable superconducting filter without distortions would be realized using this film with high power-handling ability.

英文关键词： superconducting filter;superconducting film;superconducting materials fabrication;characteristic test