Abstract

We have developed a new femtosecond-resolved optical technique with which one may examine magnetic spin dynamics in near-atomic scale structures by employing a highly sensitive, ultrafast measurement of the Faraday rotation. We apply this spectroscopy to novel band-gap-engineered II–VI diluted magnetic semiconductor heterostructures of two types to demonstrate the ability to simultaneously monitor electronic and magnetic interactions in a quantum geometry. The experiments show that these dynamics evolve on widely different time scales, and reveal the onset and decay of magnetization due to carrier spin scattering with femtosecond temporal resolution (300 fs). Although photoexcited carriers recombine within several hundred picoseconds, they leave behind a magnetic ‘‘footprint’’ that persists considerably longer and relaxes through an entirely different spin-lattice mechanism. Time-resolved magnetic measurements reveal the unusual dynamical properties of low-dimensional systems incorporating magnetic spins as compared to traditional semiconductor heterostructures.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.