Austin Koch, an REU (Rese
arch Experience for Undergraduates) participant, gave a poster presentation on August 5 at the Chemistry Atrium in Henry Eyring Building. His work focused on the nanoscale compositional analysis of topological insulators and 3D Dirac semimetals.
The samples were provided by Prof. Taylor Sparks (MSE) and Prof. Vikram Deshpande (Physics). The high-resolution STEM/EDX measurements were performed in the Utah Nanofab. Thank for the great help from the TEM experts (Dr. Jeffery Aguiar, Dr. Brian Devener) and Yoon’s Research Group members (Eric Snyder, Alvaro Bonilla, Dean Collett, Zijian, Wang).
Abstract: Topological insulators are a new class of materials in which the surface has a high conductivity similar to graphene, while the interior bulk has an insulating property. In order to realize the high performance optoelectronic devices, homogeneous materials are required. In this work, we investigated the surface and interior bulk properties of two materials (Cd3As2 Dirac semimetal and BiSbTeSe2 topological insulator) to determine local structural, compositional or fabrication-based anomalies.