CAREER: Time-Resolved Studies of Correlated Electronic Materials

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This Faculty Early Career Development (CAREER) project at the University of Pennsylvania will study magnetic instabilities related to the carrier density in strongly interacting (correlated) electronic systems using state-of-the art ultrafast optical experiments. Short (100 fs) laser pulses will modulate the carrier concentration in colossally magnetoresistive oxides and weakly ferromagnetic divalent hexaborides, thereby perturbing their complex many-body states. A variety of time-resolved optical techniques will be utilized to obtain a multi-dimensional view of the ensuing magnetic, charge and lattice dynamics. If successful, the insight obtained may help guide the discovery of related materials of use in technological applications involving magnetoresistance and the optical control of ferromagnetic order. The educational component of this project will prototype and deploy captivating and entertaining internet-based experiments that introduce high school students to the process of scientific discovery. Students arriving at a web site will be given the opportunity to remotely grab the controls of an apparatus and to experiment with them. Considerable attention will be paid to experimental design considerations, including educational value, scalability, integration with course content, and target age groups. %%%New and poorly understood magnets have been discovered recently, and this Faculty Early Career Development (CAREER) project at the University of Pennsylvania aims to clarify their behavior using short laser pulses. The unusual properties of these magnets create the possibility that, with proper materials design, light could be used to control their magnetic strength and the positions of their north and south magnetic poles. Another potential use is in magnetic recording, where related materials could serve as sensors in computer hard disk drives. This project aims to provide a foundation of knowledge for such efforts by capturing a variety of material responses to brief laser excitation. The educational component of this project will prototype and deploy captivating and entertaining internet-based experiments that introduce high school students to the process of scientific discovery. Students arriving at a web site will be given the opportunity to remotely grab the controls of an apparatus and to experiment with them. Considerable attention will be paid to experimental design considerations, including educational value, scalability, integration with course content, and target age groups. ***