title: Long-range superharmonic Josephson current and spin-triplet pairing correlations in a junction with ferromagnetic bilayers.
abstract: The long-range spin-triplet supercurrent transport is an interesting phenomenon in the superconductor/ferromagnet () heterostructure containing noncollinear magnetic domains. Here we study the long-range superharmonic Josephson current in asymmetric junctions. It is demonstrated that this current is induced by spin-triplet pairs  -  or  +  in the thick layer. The magnetic rotation of the particularly thin layer will not only modulate the amplitude of the superharmonic current but also realise the conversion between  -  and  + . Moreover, the critical current shows an oscillatory dependence on thickness and exchange field in the layer. These effect can be used for engineering cryoelectronic devices manipulating the superharmonic current. In contrast, the critical current declines monotonically with increasing exchange field of the layer, and if the layer is converted into half-metal, the long-range supercurrent is prohibited but still exists within the entire region. This phenomenon contradicts the conventional wisdom and indicates the occurrence of spin and charge separation in present junction, which could lead to useful spintronics devices.
authors.affiliation: Department of Physics, South University of Science and Technology of China, Shenzhen, 518055, China.|School of Physics and Telecommunication Engineering, Shaanxi University of Technology, Hanzhong 723001, China.|National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Meng
authors.affiliation: Department of Physics, South University of Science and Technology of China, Shenzhen, 518055, China.
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Wu
authors.affiliation: National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China.
authors.forename: Xiuqiang
authors.initials: X
authors.lastname: Wu
authors.affiliation: School of material science and technology, Harbin university of science and technology, Harbin 150080, china.
authors.forename: Mengyuan
authors.initials: M
authors.lastname: Ren
authors.affiliation: School of Physics and Telecommunication Engineering, Shaanxi University of Technology, Hanzhong 723001, China.
authors.forename: Yajie
authors.initials: Y
authors.lastname: Ren