We report the fabrication and testing, at 4.2 K, of an SISFS device, where S, F, and I denote a superconductor (Nb), a ferromagnetic material (permalloy), and an insulator (AlOx), respectively. The F layer covers about one half of the top electrode of the SIS Josephson junction and is positioned off-center. Electric current, I _tr, along the S electrode can change the magnetization of the F layer in such a way that, for one direction of I_tr, a magnetic flux penetrates the junction perpendicular to the layers, whereas for the opposite direction, the perpendicular magnetic flux can be removed. In the former state, the modulation pattern of the Josephson critical current, Ic, in the magnetic field, H, may acquire minimum near H=0, and restores its usual shape with maximum in the second state. These states can be used for building a compact cryogenic memory compatible with single flux quantum electronics.
Higher-Order Topological Superconductivity and Electrically Tunable Majorana Corner Modes in Monolayer MnXPb$_2$ (X=Se, Te)-Pb Heterostructure
Institute of Applied Physics and Computational Mathematics（应用物理与计算数学研究所）；Anhui Provincial Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences（中国科学院合肥物质科学研究院强磁场科学中心安徽低能量子材料与器件重点实验室）；Science Island Branch of Graduate School, University of Science and Technology of China（中国科学技术大学研究生院合肥科学岛分院）；National Key Laboratory of Computational Physics（计算物理学国家重点实验室）；School of Physics and Physical Engineering, Qufu Normal University（曲阜师范大学物理工程学院）
Critical Current Oscillations of Elliptical Josephson Junctions with Single-Domain Ferromagnetic Layers
含有铁磁层的约瑟夫森结对于开发实用的低温存储器和超导量子比特具有相当大的兴趣。对于一定范围的铁磁层厚度，这种结表现出$π$的相移。我们目前的研究铌基微米级椭圆形约瑟夫森结含有铁磁势垒的Ni $_{81}$ Fe $_{19}$或Ni $_{65}$ Co $_{20}$ Fe $_{15}$。通过施加一个外部磁场，结的临界电流被发现遵循特征夫琅和费图案，并显示尖锐的切换行为暗示单畴磁铁。高质量的夫琅和费图案使我们能够提取的临界电流的最大值，即使当峰值被转移到数据的范围外，由于铁磁层的磁矩显着。临界电流的最大值作为铁磁势垒厚度的函数振荡，指示在零和$π$的值之间跨越结的相位差的转变。我们比较的数据，以前的工作和现有理论的基础上的0- $π$转换的模型。
Hybrid Ferromagnet-SNSPDs: Single photon induced order-to-disorder transition in ferromagnets coupled to thin film superconductors
The Elmore Family School of Electrical and Computer Engineering, Purdue University（普渡大学埃尔莫电气与计算机工程学院）；Department of Physics, Worcester Polytechnic Institute（伍斯特理工学院物理系）
