CAREER: Quantum Tunneling in Superconducting and Ferromagnetic Nanoscale Structures

*非技术摘要*这个学院早期职业奖支持一个项目，其目的是详细了解一维(1D)超导导线以及一维和零维铁磁结构中的量子现象。该项目的直接动机是将纳米级出现的新物理学融入到更好、更功能的材料和设备的设计中。具体地说，一维超导体保持高磁场的独特能力可以被用来设计更紧凑的超导磁体，并将导致更有效的电力传输和分配。对一维超导体物理的详细了解可以提供新的方法来控制并实际上增强纳米尺度的超导电性，例如通过耦合到耗散环境。铁磁结构的研究结果可能会影响磁记录的实际应用。研究生和本科生将参与一项令人兴奋的多学科研究，涵盖物理、材料科学、纳米技术和电气工程。还将向当地高中科学教师和高中生提供小型项目，他们将参与夏季磁学研究。新的本科课程？现代技术和生命科学的物理核心？将会被开发出来。这门课程将通过精心挑选具有重要技术意义的设备和结构的例子来加强电磁学、量子力学和统计力学的核心知识。*技术摘要*这个学院早期职业生涯奖支持一个项目，目的是发展对一维超导导线、一维和零维铁磁结构中的量子现象的详细了解。该项目的直接动机是将纳米级出现的新物理学融入到更好、更功能的材料和设备的设计中。一维纳米线的超导体-绝缘体转变机制将通过磁场连续驱动跨越临界区的转变来研究。将开发一种高采样率的技术来检测单个相移，并将研究热相移和量子相移之间的时间关联。耗散对量子相位滑移的影响将通过改变导线的电磁环境来阐明。通过在悬浮的绝缘碳纳米管上沉积钴、坡莫合金和稀土磁性合金，可以制备一系列均匀的铁磁纳米线。这些导线将被用来测试极度受限的磁畴壁的特性。将进行低温输运测量，以寻找这些导线中的量子成核和量子去钉扎。研究生和本科生将参与一项令人兴奋的多学科研究，涵盖物理、材料科学、纳米技术和电气工程。还将向当地高中科学教师和高中生提供小型项目，他们将参与夏季磁学研究。一门新的本科课程将通过精心挑选具有重要技术意义的设备和结构的例子来加强电磁学、量子力学和统计力学的核心知识。

****NON-TECHNICAL ABSTRACT**** This Faculty Early CAREER award supports a project with an objective to develop detailed understanding of quantum phenomena in one-dimensional (1D) superconducting wires and in one and zero-dimensional ferromagnetic structures. The project is directly motivated by prospects of incorporating new physics that emerges at the nanoscale into the design of better, more functional materials and devices. Specifically, the unique ability of one-dimensional superconductors to sustain high magnetic fields could be utilized in the design of more compact superconducting magnets and would result in more efficient transmission and distribution of electric power. Detailed understanding of the physics of 1D-superconductors could provide new methods of controlling and, in fact, enhancing superconductivity at the nanoscale, for example by coupling to a dissipative environment. The outcome of the study on the ferromagnetic structures may influence practical applications in magnetic recording. Graduate and undergraduate students will be involved in an exciting multi-disciplinary research that covers physics, material sciences, nanotechnology and electrical engineering. Small projects will be also offered to local high school science teachers and high school students who will be involved in summer research on magnetism. A new undergraduate course ?Physics Core of Modern Technology and Life Science? will be developed. The course will reinforce the core knowledge of electromagnetism, quantum mechanics and statistical mechanics with carefully selected examples of technologically important devices and structures.****TECHNICAL ABSTRACT****This Faculty Early CAREER award supports a project with an objective to develop detailed understanding of quantum phenomena in one-dimensional superconducting wires and in one and zero-dimensional ferromagnetic structures. The project is directly motivated by prospects of incorporating new physics that emerges at the nanoscale into the design of better, more functional materials and devices. The mechanism of superconductor-insulator transition in 1D nanowires will be investigated by continuously driving the transition across the critical regime with a magnetic field. A high sampling-rate technique for detection of individual phase slips will be developed and temporal correlations between thermal and quantum phase slips will be studied. The effect of dissipation on quantum phase slips will be elucidated by varying the electromagnetic environment of a wire. A series of homogeneous ferromagnetic nanowires will be fabricated by depositing cobalt, permalloy and rare earth magnetic alloys on top of suspended insulated carbon nanotubes. The wires will be used to test properties of extremely constrained magnetic domain walls. Low temperature transport measurements will be carried out in search for quantum nucleation and quantum depinning of domain walls in these wires. Graduate and undergraduate students will be involved in an exciting multi-disciplinary research that covers physics, material sciences, nanotechnology and electrical engineering. Small projects will be also offered to local high school science teachers and high school students who will be involved in summer research on magnetism. A new undergraduate course will reinforce the core knowledge of electromagnetism, quantum mechanics and statistical mechanics with carefully selected examples of technologically important devices and structures.