Al/AlOx/Al约瑟夫森结阵列中的结构无序与临界电压标度
Structural disorder and critical voltage scaling in Al/AlOx/Al Josephson junction arrays
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中文总结 AI 辅助
本研究探究制备诱导结构缺陷对Al/AlOx/Al约瑟夫森结阵列临界电压标度的影响，明确了不同结构修改对集体输运的作用，为量子滑移器件设计提供指导。
中文摘要 AI 辅助
一维约瑟夫森结（JJ）阵列的绝缘态由集体电荷动力学和无序诱导钉扎所主导，在直流偏置下会产生有限的临界电压。本研究探究了制备诱导的结构缺陷对小电容铝-氧化铝-铝（Al/AlOx/Al）JJ阵列临界电压标度的影响。通过控制铝蒸发速率，可显著改变晶粒形貌与室温结电阻。尽管存在这些显著的结构修改，归一化临界电压标度仍得以保留，表明集体输运行为对这类制备诱导缺陷具有极强的鲁棒性。相比之下，在结中刻意引入纳米级间隙会引入额外的结间结构变化，系统性地改变归一化标度行为。同样，制备后原位氧化会改变标度系数，同时保留标度律的函数形式，表明集体输运对特定类别的结构修改敏感。这些结果明确了哪些制备诱导的结构缺陷会影响绝缘Al/AlOx/Al约瑟夫森结阵列中的集体输运，为制备诱导结构无序的作用提供了新见解，并为未来量子滑移（QPS）器件的设计提供了实用指导。
英文摘要
The insulating state of one-dimensional Josephson junction (JJ) arrays is governed by collective charge dynamics and disorder-induced pinning, resulting in a finite critical voltage under dc bias. Here, we investigate the influence of fabrication-induced structural defects on the critical-voltage scaling of small-capacitance Aluminium-Aluminium oxide-Aluminium (Al/AlOx/Al) JJ arrays. Controlled variation of the aluminium evaporation rate produces pronounced changes in grain morphology and room-temperature junction resistance. Despite these substantial structural modifications, the normalised critical-voltage scaling is preserved, demonstrating that the collective transport behaviour is remarkably robust against this class of fabrication-induced defects. In contrast, the deliberate introduction of nanoscale gaps into the junctions introduces additional junction-to-junction structural variations that systematically modify the normalised scaling behaviour. Likewise, in situ postfabrication oxidation alters the scaling coefficient while preserving the functional form of the scaling law, indicating that the collective transport is sensitive to specific classes of structural modifications. These results establish which fabrication-induced structural defects influence the collective transport in insulating Al/AlOx/Al Josephson junction arrays, providing new insight into the role of fabrication-induced structural disorder and practical guidance for the design of future Quantum Phase Slip (QPS) devices.
