A Spin Torque Oscillator Maser Device Enabled by Spin-Microwave Photon Coupling

能够在微波频率范围内产生信号的设备现在对于电信，雷达和量子计算技术至关重要。 迫切需要紧凑且高性能的器件，这些器件可以很容易地与其他经典或量子电路相结合。该提案提出通过应用微波信号与磁性材料之间的相互作用产生的新机制来探索实现新的微波源装置的可能性，该微波源装置将具有比现有微波源装置更上级的性能。拟议的研究如果成功，不仅会促进科学领域的进步，而且会产生教育影响，通过开发课程单元，吸引各个层次的学生，特别是来自社会经济弱势群体的学生，学习应用物理学和电子工程学，提高学生对量子科学的理解。推广活动包括激发广大公众对磁性器件领域令人兴奋的机会的认识。该项目中使用的方法是基于自旋扭矩振荡器的现象，这是一种很有前途的技术，用于实现片上微波源，检测器和神经形态计算设备。现有的自旋力矩振荡器存在输出功率低、线宽宽以及需要复杂的外部支持电路等问题，极大地限制了其实际应用。为了克服这些困难，本研究提出了一种在微波谐振腔中放置自旋力矩振荡器，实现大面积铁磁薄膜相干磁自振荡的新方法。磁体和微波谐振器之间的相互作用将导致它们的振荡动力学之间的耦合，这将进一步导致在非常大面积的磁性自由层中的宏观相位相干。通过制造所提出的器件结构并测试微波输入-输出关系，所提出的器件结构不仅将导致新颖的相干、高功率、片上微波源，该奖项反映了NSF的法定使命，并通过使用基金会的知识产权进行评估，被认为值得支持。优点和更广泛的影响审查标准。

Devices that can generated signals in the microwave frequency range are vital for now a days for telecommunication, radar and quantum computing technologies. There is a critical need for compact and high-performance devices that can be easily combined with other classical or quantum circuit. This proposal proposes to explore the possibility of realizing a new microwave source device that will have superior performance over existing ones, by applying new mechanisms resulting from the interactions between microwave signal and magnetic materials. The proposed research, if successful, will not only lead to advancement in the scientific areas, but also have educational impact by developing course modules that will enhance students’ understanding on quantum science by attracting students at all levels, particularly from socio-economically disadvantaged groups, into the study of applied physics and electronic engineering. Outreach activities include inspiring broad public awareness in the exciting opportunities in magnetic device domains. The approach used in the project is based on the phenomenon of spin torque oscillator, which is one promising technique for realizing on-chip microwave sources, detectors, and neuromorphic computing devices. Existing spin torque oscillators suffer from challenges in low output power, broad linewidth as well as the requirement for complicated external supporting circuits, which greatly limits their practical applications. In this project, to overcome these difficulties, a new approach for realizing coherent magnetic self-oscillation in a large area ferromagnetic thin film by placing a spin torque oscillator into a microwave resonator is conceived. The mutual interactions between the magnet and microwave resonator will lead to a coupling between their oscillation dynamics, which will further result in macroscopic phase coherence in magnetic free layer with very large area. By fabricating the proposed device structures and testing on the microwave input-output relationship, the proposed device structure will not only result in a novel coherent, high power, on-chip microwave source, but also enrich people’s understanding on spin dynamics and the coupling physics between magnets and microwave.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.