Recent breakthroughs in understanding of current-induced magnetization dynamics in nano-structures have led to the emergence of a new type of microwave spin-torque nano-oscillatorssources. The goal of this collaborative research program is to create experimental prototypes and develop a theory of operation of two novel microwave signal-processing devices that are based on spin-torque nano-oscillators : (i) ultra-fast broadband spectrum analyzer;(ii) on-chip microwave signal modulator. The proposed devices are based on a new oscillator geometry with two ?free? magnetic layers. In this geometry, the free layers precess in directions opposite to each other, thus doubling the frequency of the generated microwave signal. This novel geometry will pave the way towards the development of oscillator-based devices with operation frequency of up to 80 gigahertz. Another goal of this program is to research the possibilities for wireless on-chip and chip-to-chip communications between the developed nano-sized devices, that will allow them to exchange and process microwave signals without high-resistance power-inefficient wire interconnects.
Intellectual merit: The proposed research program will have a transformative impact on the field of microwave nano-spintronics, and will lead to the development of a new concept of nano-sized on-chip microwave signal processing devices with wireless communication capabilities. The development of this transformative concept could change the way system engineers think about integration of individual nano-scale devices into nano-spintronic integrated circuits. The proposed research will also advance our understanding of the physics of interactions between spin-polarized currents and dynamic magnetization in magnetic nanostructures. The approach is to use the full benefit of synergistic interaction between the experimental group at the University of California, Irvine and the theoretical group at the Oakland University. This collaborative effort will be enhanced by interactions with leading US and European research groups, and with leading domestic industrial partners to achieve a breakthrough in the development of device technology for microwave nano-spintronics.
Broader impacts: The proposed research program will impact society in multiple ways. The new types of microwave on-chip nano-scale signal processing devices developed in this program will help maintain US leadership in microwave electronics. A number of undergraduate and graduate students will be exposed to the modern methods of nanoscience and nanotechnology, and will interact with the leading foreign and domestic research groups, as well as with our industrial partners. The proposed program will prepare valuable specialists for the US electronics and magnetic recording industries that are currently undergoing a rapid transition from the micro- to the nano-scale, and will enhance the US research infrastructure. A special mentoring program for post-doctoral researchers, educating them on writing research proposals and organizing collaborative research, will prepare our postdocs for the future independent scientific careers. The outreach activities (lectures and demonstrations on nanoscience and nanotechnology tailored for K-12 teachers and students) will contribute to the development of skilled workforce and scientifically informed public. The proposed program will also create a strong impact on education as a result of incorporating theoretical and experimental methods of nanotechnology into the graduate and undergraduate university curricula by the program participants.
