In this paper, we extend the scope of numerical simulations of marine controlled-source electromagnetic (CSEM) fields in a particular case of anisotropy (dipping anisotropy) to the general case of anisotropy by using ...In this paper, we extend the scope of numerical simulations of marine controlled-source electromagnetic (CSEM) fields in a particular case of anisotropy (dipping anisotropy) to the general case of anisotropy by using an adaptive finite element approach. In comparison to a dipping anisotropy case, the first order spatial derivatives of the strike-parallel components arise in the partial differential equations for generally anisotropic media, which cause a non-symmetric linear system of equations for finite element modeling. The adaptive finite element method is employed to obtain numerical solutions on a sequence of refined unstructured triangular meshes, which allows for arbitrary model geometries including bathymetry and dipping layers. Numerical results of a 2D anisotropic model show both anisotropy strike and dipping angles have great influence on the marine CSEM responses.展开更多
In this work, we selected a magnetic-semiconductor as an interlayer and investigated the electronic transport properties in the ferromagnetic/ferromagnetic-semiconductor/ferromagnetic (FM/FS/FM) trilayers. The results...In this work, we selected a magnetic-semiconductor as an interlayer and investigated the electronic transport properties in the ferromagnetic/ferromagnetic-semiconductor/ferromagnetic (FM/FS/FM) trilayers. The results indicate that the large TMR comparable to that in ferromagnetic/metal oxide/ferromagnetic sandwich can be obtained in the FM/FS/FM multilayers with considering the spin filter effect in the magnetic semiconductor layer. Moreover, the transmission coefficient and TMR can be tuned through thickness, Rashba spin-orbit coupling strength and molecular field of the magnetic semiconductor. Our calculations could provide a way to design the semiconductor spintronic devices with excellent and controllable properties.展开更多
基金funded by the National Natural Science Foundation of China (NO 41130420)
文摘In this paper, we extend the scope of numerical simulations of marine controlled-source electromagnetic (CSEM) fields in a particular case of anisotropy (dipping anisotropy) to the general case of anisotropy by using an adaptive finite element approach. In comparison to a dipping anisotropy case, the first order spatial derivatives of the strike-parallel components arise in the partial differential equations for generally anisotropic media, which cause a non-symmetric linear system of equations for finite element modeling. The adaptive finite element method is employed to obtain numerical solutions on a sequence of refined unstructured triangular meshes, which allows for arbitrary model geometries including bathymetry and dipping layers. Numerical results of a 2D anisotropic model show both anisotropy strike and dipping angles have great influence on the marine CSEM responses.
基金Sichuan Province Academic and Technical Leader Training Foundation (Grant No. 25727501)the Subject Construction Foundations of Southwest University for Nationalities (Grant No.2012XWD-S0805)
文摘In this work, we selected a magnetic-semiconductor as an interlayer and investigated the electronic transport properties in the ferromagnetic/ferromagnetic-semiconductor/ferromagnetic (FM/FS/FM) trilayers. The results indicate that the large TMR comparable to that in ferromagnetic/metal oxide/ferromagnetic sandwich can be obtained in the FM/FS/FM multilayers with considering the spin filter effect in the magnetic semiconductor layer. Moreover, the transmission coefficient and TMR can be tuned through thickness, Rashba spin-orbit coupling strength and molecular field of the magnetic semiconductor. Our calculations could provide a way to design the semiconductor spintronic devices with excellent and controllable properties.
