We study numerically the phase diagram and the response under a driving force of the phase field crystal model for pinned lattice systems introduced recently for both one and two dimensional systems. The model describes the lattice system as a continuous density field in the presence of a periodic pinning potential, allowing for both elastic and plastic deformations of the lattice. We first present results for phase diagrams of the model in the absence of a driving force. The nonlinear response to a driving force on an initially pinned commensurate phase is then studied via overdamped dynamic equations of motion for different values of mismatch and pinning strengths. For large pinning strength the driven depinning transitions are continuous, and the sliding velocity varies with the force from the threshold with power-law exponents in agreement with analytical predictions. Transverse depinning transitions in the moving state are also found in two dimensions. Surprisingly, for sufficiently weak pinning potential we find a discontinuous depinning transition with hysteresis even in one dimension under overdamped dynamics. We also characterize structural changes of the system in some detail close to the depinning transition.
Strong enhancement of critical current density in both low & high fields and flux pinning mechanism under hydrostatic pressure in optimally doped (Ba,K)Fe2As2 single crystals
Direct observation of nanometer-scale pinning sites in (Nd$_{0.33}$,Eu$_{0.20}$,Gd$_{0.47}$)Ba$_2$Cu$_3$O$_{7-δ}$ single crystals
本文报道了在（Nd，Eu，Gd）Ba $_2$ Cu $_3$ O $_y$单晶体表面和体内观察到的自组织条纹状结构。表面上条纹的周期性在500和800 nm之间。这些可能是晶体的生长步骤。透射电子显微镜的调查显示，在20至40 nm的范围内的散装周期性条纹。从电子背散射衍射调查，没有晶体学取向不良，由于nanostripes.Scanning隧道光谱实验发现非超导区域，沿孪晶方向，这大概构成强钉扎网站。
Angle-dependent Magnetoresistance of an Ordered Bose Glass of Vortices in YBa$_{2}$Cu$_{3}$O$_{7-δ}$ Thin Films with a Periodic Pinning~Lattice
超导$_{2}$ O $_{7-δ}$（YBCO）薄膜中的本征无序与超致密三角形晶格的30 nm间距的钉扎中心之间的竞争导致有序的玻色玻璃相涡旋。通过在YBCO薄膜的表面上扫描氦离子显微镜的聚焦光束以形成点缺陷的列，其中超导性被局部抑制，来创建样品。的电压-电流等温线揭示了临界行为和规模在附近的二级玻璃化转变。后者表现出一个明显的峰值，在熔融温度（$T_g$）与施加的磁场（$B_a$）在磁可磁化率场，随着玻璃波动的寿命急剧上升。在恒定的洛伦兹力的几何形状的角度相关的磁阻测量揭示了一个强大的各向异性增加相比，一个原始的参考膜的涡旋的密度相匹配的柱状缺陷。因此，钉扎由平行于柱状缺陷的磁场分量主导，暴露出其一维特征。这些结果支持有序玻色玻璃相的想法。
