CAREER: In situ Optical and Magnetotransport Studies of Organic-Ferromagnetic-Semiconductor Hybrid Structures for Spin-Based Electronics

University Of California-Riverside, Riverside CA

Investigators

Abstract

This project investigates spin-dependent phenomena in novel hybrid structures that combine organic semiconductors with ferromagnetic films and semiconductor heterostructures. This is a fascinating new direction for the field of spintronics (spin-based electronics) and there are great opportunities to realize new physical phenomena due to the unusual properties of organic molecules, such as adjustable spin-orbit coupling and asymmetric spin scattering by chiral molecules. To explore these and other possibilities, molecular beam epitaxy synthesis is combined with in situ optical, ultrafast optical, and magnetotransport characterization. In this manner, high quality layered structures are fabricated in ultrahigh vacuum with atomic-scale precision, and the evolution of the electronic and spin-dependent properties can be investigated at different stages of fabrication. The long term technological impact of this work is in the areas of information storage, computing, optoelectronics, and flexible displays. The participation of graduate students, undergraduates, high school students and teachers in this cutting-edge materials research will provide education and training in high-technology areas which have been previously unavailable in the Inland Empire of Southern California. This project also leads the nascent electronic/magnetic/optical materials research effort at the rapidly growing UC Riverside campus through new coursework and research infrastructure development. The development of electronics in the latter half of the 20th century (which is responsible for computers, CD/DVD players, cell phones, etc.) is based on moving electrons from one location to another in an electronic circuit. In the last 15 years, scientific breakthroughs have enabled the "spinning" motion of electrons (similar to the rotation of a basketball) to be exploited for new technologies such as giant magnetoresistive read heads used in computers hard drives and multimedia applications. This new paradigm for electronics has come to be known as spintronics. This project develops new hybrid materials that combine traditional inorganic electronic materials (gallium arsenide, silicon, iron, etc.) with organic molecular films to take advantage of electron spin as never before possible in purely inorganic materials. This is a fascinating new direction for spin-based electronics research. These hybrid structures will be created by a process called molecular beam epitaxy in which materials are deposited atom-by-atom or molecule-by-molecule in an ultrahigh vacuum environment for the most well-controlled, highest purity materials and structures. The behavior of electrons and their spinning motion will be investigated using state-of-the-art optical and electronic tools. This research may lead to advances in computing, data storage, optoelectronics, and displays. The participation of graduate students, undergraduates, high school students and teachers in this cutting-edge materials research will provide education and training in high-technology areas which have been previously unavailable in the Inland Empire of Southern California. This project also leads the nascent electronic/magnetic/optical materials research effort at the rapidly growing UC Riverside campus through new coursework and research infrastructure development.