Nonlinear Vortex Dynamics in Superconductors with Anisotropic Pinning Nanostructures

薄膜中单轴或双各向异性钉扎结构的制备为控制第二类超导体的混合态电阻响应开辟了一条受控途径，有望将其用于磁通学应用，即操纵类似于纳米和微电子中的电子的单涡。此外，这种薄膜在描述各向异性钉扎影响下的非线性涡旋动力学的最新理论方法中提供了一个具有完全可预测特性的模型系统。从电阻率数据推导各向异性钉扎势参数将首次允许回答以下问题：在哪个频率范围内产生的谐波最明显？如何优化特殊的(双各向异性和非对称棘轮)纳米结构，为微波器件制造提供最合适的钉扎电势特性？霍尔效应和棘轮效应之间是否存在干扰效应？为了回答这些问题，将使用原始的旋转电流方案，并采用特殊的不对称信号平均方法。预期的结果不仅对薄膜超导体有意义，而且对所有类似的受到直流和交流电流驱动的噪声中介系统也是通用的。

The fabrication of uniaxial or bianisotropic pinning structures in thin films opens up a controlled pathway to govern the mixed-state resistive response of type-II superconductors with a perspective of using it for fluxonics applications, i. e. manipulating single vortices similar to electrons in nano- and microelectronics. Moreover, such films provide a model system with fully predictable properties within a state-of-the-art theoretical approach of describing the nonlinear vortex dynamics under the influence of anisotropic pinning. The deduction of anisotropic pinning potential parameters from resistivity data will allow for the first time to answer the following questions: In which frequency range is a harmonic generation most pronounced? How can one optimize special (bianisotropic and asymmetric-ratchet) nanostructures to provide the most suitable pinning potential characteristics for microwave device fabrication? Is there an interference effect between the Hall- and the ratchet-effect? In order to answer these questions an original rotating-current scheme will be used and special methods for asymmetric signal averaging be applied. The expected results are of interest not only for thin-film superconductors but they will be generic to all similar noise-mediated systems subjected to DC and AC current driving.