Publications [#63857] of Lawrence Carin
Papers Published
- Melloch, M.R. and Harmon, E.S. and Woodall, J.M. and Nolte, D.D. and Carin, L. and Kralj, D.R. and Chang, J.C.P. and Otsuka, N.. "Cluster engineering for photoconductive switches." Ultra-Wideband, Short-Pulse Electromagnetics 2. Proceedings of the Second International Conference (1995): 25 - 31.
(last updated on 2007/04/14)Abstract:
We demonstrate the ability to engineer composites of metallic As clusters in arsenide semiconductor matrices by using the substrate temperature during MBE to set the amount of excess As in the epilayer and a subsequent nucleation/coarsening anneal. The carrier lifetime is shown to be a strong function of the As cluster spacing and hence a controllable parameter. These composites were used to photoconductively switch coplanar strip horn antennas. There was a strong increase in peak radiated pulse intensity with decrease in As cluster spacing probably due to an increase in carrier mobility. Although carrier lifetimes increase with increase in As cluster spacing, for our applications with 5 ps excitation pulses this did not adversely affect the shape of our radiated pulses for the composites we investigated. Therefore, for a given application as a photoconductive switch, one can engineer the composite structure for optimum carrier lifetime and mobility. An interesting alternative for forming composites with other metals using ion implantation followed by a nucleation/coarsening anneal was also demonstrated