The consequences of the random pinning in the presence of weak disorder are studied systematically based on the appearance of the second magnetization peak (SMP) and peak effect in the magnetic measurement. Here, we have observed the system dependency of the SMP effect. We have analysed the dc magnetization curves and the associated vortex pinning mechanisms of V_0.0007NbSe₂ single crystal at different temperatures and magnetic fields to estimate its pinning strengths in the external magnetic field H oriented parallel to the crystallographic ab plane. The characteristics of critical current density result in the presence of weak collective pinning near zero-magnetic field and the large bundle collective pinning along with SMP effect at the intermediate magnetic fields. The field dependence characteristics of the pinning force density highlights the presence of Bean-Livingstone’s zero-field peak with the presence of intermediate peak and high-field peak effect phenomena. The temperature dependence of the critical current density shows the dominating nature of δl pinning in the intermediate fields region. The vortex phase diagram of V_0.0007NbSe₂ is drawn showing different vortex phases at altered temperatures and magnetic fields. Thus, this study depicts the SMP effect and the diverse pinning characteristics in the quasi-two-dimensional superconductor associated with the external defects.

中文翻译：

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V 0.0007 NbSe 2单晶中的无序诱发的第二磁化峰效应和涡旋钉扎机理

基于第二磁化峰（SMP）的出现和磁测量中的峰效应，系统地研究了存在弱无序情况下随机钉扎的后果。在这里，我们观察到了SMP效应的系统依赖性。我们分析了V _0.0007 NbSe ₂单晶在不同温度和磁场下的直流磁化曲线和相关的旋流钉扎机制，以估计其在平行于晶体学ab的外部磁场H中的钉扎强度飞机。临界电流密度的特性导致在零磁场附近存在弱的集体钉扎和在中间磁场处伴随着SMP效应的大束集体钉扎。钉扎力密度的场相关特性突出了Bean-Livingstone零场峰的存在以及中间峰和高场峰效应现象的存在。临界电流密度的温度依赖性显示了在中间场区域中δl钉扎的主要性质。V _0.0007 NbSe ₂的旋涡相图图中显示了在变化的温度和磁场下不同的涡旋相。因此，本研究描述了与外部缺陷相关的准二维超导体中的SMP效应和不同的钉扎特性。