AI 中文总结
本研究实现了PbSe在GaAs上8%晶格失配下的选择性区域生长，获得高取向、低缺陷纳米结构，并展示了中红外发射和栅极可调约瑟夫森结，为可扩展量子平台奠定基础。
AI 中文摘要
PbSe的选择性区域生长有望实现高密度、缺陷容忍的纳米结构网络的可确定位置放置，从而迈向可扩展的量子平台。PbSe是一种窄带隙半导体，具有优异的（光）电子特性，已被证明具有良好的缺陷容忍性，即使在高度不相似的平台上生长也能实现明亮发射，并且可以与选择性生长相结合，用于位点选择性量子发射器和低无序混合纳米线网络。在本工作中，尽管存在8%的大晶格失配，我们仍实现了具有良好晶面和有序性的PbSe纳米结构的位点选择性生长。结构和形貌表征显示，在100纳米开口内，超过99%的选择性生长岛为单一取向，且以立方对立方方式取向，表面均方根粗糙度低于亚纳米级。缺陷分析表明，74%的岛和86%的不同掩模开口之间的聚结区域没有穿透位错。尽管这些PbSe岛具有比平面控制样品更高的表面积与体积比，它们在中红外区域仍实现了等效发射。此外，我们展示了利用本研究中确定的生长条件生长的PbSe纳米线制备的栅极可调双端约瑟夫森结。可访问的选择性生长区域、岛生长的形貌控制以及光学和电学输运性质的演示相结合，表明PbSe SAG作为缺陷容忍的可扩展量子平台具有前景。
英文摘要
Selective area growth of PbSe has the potential to realize deterministic placement of high-density, defect-tolerant nanostructure networks toward a scalable quantum platform. PbSe is a narrow bandgap semiconductor with advantageous (opto)electronic properties that has been shown to have a desirable defect-tolerance, enabling bright emission even when grown on highly-dissimilar platforms, and could be leveraged in combination with selective growth for site-selective quantum emitters and low-disorder hybrid nanowire networks. In this work, we achieve site-selective growth of well-faceted and ordered PbSe nanostructures, despite a large 8% lattice mismatch. Structural and morphological characterization reveal that $>$99% of selectively grown islands within 100 nm opening are single-orientation and cube-on-cube oriented with sub-nm root-mean-square surface roughness. Defect analysis showed that 74% of the islands and 86% of the coalesced regions between different mask openings were free of threading dislocations. These PbSe islands achieved equivalent emission in the mid-infrared despite having a higher surface-to-volume ratio than the planar control. Further, we present a gate-tunable two-terminal Josephson junction fabricated from the PbSe nanowires grown with conditions identified in this study. The combination of the accessible selective growth regime, morphological control of island growth and demonstrations of optical and electrical transport properties indicates promise for PbSe SAG as a defect-tolerant scalable quantum platform.
Comments26 pages, 5 figures
