Development of: High Resolution, High Sensitivity Scanning Josephson Junction Microscope

开发：高分辨率、高灵敏度扫描约瑟夫森结显微镜

• 批准号: 0079583
• 负责人: Rajeev Ram
• 金额: $ 17.5万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0079583&HistoricalAwards=false
• 关键词: Development; Resolution; Sensitivity; Scanning; Josephson

This proposal is for the development of a high resolution, high sensitivitymagnetic field imaging microscope. This instrument will allow for themeasurement of minute magnetic fields (10-5 G) generated by currents inmesoscopic devices, the magnetic properties of quantum structures and thespin states of electrons inside devices. The instrument will be the firstscanning Josephson junction microscope (SJM). It will have six orders ofmagnitude higher field sensitivity than conventional magnetic forcemicroscopy and an order of magnitude better spatial resolution thanscanning SQUID microscopy.In order to build this tool, the expertise of several groups at MIT must bebrought together. The Josephson junction (JJ) that forms the criticalsensing element must be integrated on an atomic force microscope tip inorder to be in sufficient proximity to the sample. This process willrequire the development of a micromechanical silicon submount onto whichthe JJ will be processed. Once the sensing element has been fabricated itmust be integrated into a larger instrument composed of cryogenicallycooled piezo-stages and circuits to monitor and amplify the signals fromthe JJ. When completed, the combination of high field sensitivity andhigh spatial resolution will allow for the study of vortex states insuperconductors, charge transport in circuits and biological systems, themagnetic state of mesoscopic magnets, and the spin state of electrons indevices.Finally, the development of a new scanning probe microscope offers excitingopportunities for interdisciplinary education. Already, students workingon device processing, circuit design, mesoscopic device physics andmaterials science have all participated in the development of the coretechnologies.

该提案旨在开发高分辨率、高灵敏度的磁场成像显微镜。 该仪器将能够测量介观器件中电流产生的微小磁场（10-5 G）、量子结构的磁特性以及器件内部电子的自旋态。 该仪器将是第一台扫描约瑟夫森结显微镜（SJM）。 它将具有比传统磁力显微镜高六个数量级的场灵敏度，比扫描 SQUID 显微镜高一个数量级的空间分辨率。为了构建这个工具，必须汇集麻省理工学院多个小组的专业知识。 形成临界传感元件的约瑟夫森结 (JJ) 必须集成在原子力显微镜尖端上，以便足够接近样品。 该工艺需要开发微机械硅基座，JJ 将在该基座上进行加工。 传感元件制造完成后，必须将其集成到由低温冷却压电级和电路组成的更大仪器中，以监控和放大来自 JJ 的信号。 完成后，高场灵敏度和高空间分辨率的结合将允许研究超导体中的涡旋态、电路和生物系统中的电荷传输、介观磁体的磁态以及器件中电子的自旋态。最后，新型扫描探针显微镜的开发为跨学科教育提供了令人兴奋的机会。 目前，器件加工、电路设计、介观器件物理和材料科学专业的学生都参与了核心技术的开发。