Materials Science Research Seminar Series


Spring 2019 Seminar Series

Fred Rueggeberg 

 Materials science applied to dentistry - an overview

Fred Rueggeberg, DDS, MS
Professor and Section Director, Dental Materials
Department of Restorative Sciences
Dental College of Georgia at Augusta University
February 22, 2019
2:30 - 3:30
Science Hall W1002

For 150 years, researchers (as well as clinician-scientists) have searched for an “ideal restorative material.” Included materials include metals, polymers, and ceramics available as an astonishing array of products. Not only are definitive restorative products a primary focus of interest, but, in addition the many types of materials used in order to generate the final restorative products involve a tremendous amount of materials science consideration: impression materials, dental stones, casting investments, waxes, photocuring devices, color measurement instruments, color-corrected lighting conditions, soldering (brazing), to name a few. And now, with the introduction of digital technology, we are dealing with 3D additive and subtractive processes: digital printing and milling. The contemporary clinician must keep up to date with all these technologies, and be able to know if and when it is advantageous to introduce costly and innovative products into his/her practice in order to keep up with the times, but also to provide predictable, long lasting restorations that the patients like (and will talk about!). Thus, this presentation will provide a short overview of the tremendous challenges facing dentists in restoring teeth, as well as the future opportunities to introduce cutting edge products into practice.

Ryan Comes

Atom-by-atom engineering of oxide thin films and nanocomposites via molecular beam epitaxy

Ryan Comes, PhD
Assistant Professor of Physics
Department of Physics
Auburn University, Auburn, Alabama
March 15, 2019
1:00 - 2:00 p.m.
Science Hall W1002

Complex oxides comprised of multiple positively charged metal cations exhibit a host of intriguing and useful properties for new technologies. Perovskite oxides with the chemical formula ABO3 and spinel oxides with the formula AB2O4 have some of the richest behavior. These materials may be metallic, semiconducting, or insulating, and exhibit ferroelectricity, with a built-in electric polarization, ferromagnetism, or superconductivity. This combination of properties in a single class of materials offers rich opportunities for engineering of unusual combinations of behavior through the design of multi-layer thin film materials. Through the use of molecular beam epitaxy (MBE), we are able to engineer these materials down to the atomic level so that interfaces between two different perovskites can be controlled to produce desirable properties. In this talk I will present two examples of this type of interfacial engineering, showing how we can design, model, and characterize these properties through a wide variety of techniques. I will discuss our work engineering interfacial termination in polar/non-polar heterojunctions and superlattices comprised of SrTiO3 and polar transition metal perovskites (LaFeO3 and LaCrO3) to engineer electric fields in these materials. In spinel-perovskite nanocomposites, we show for the first time that MBE can be used to grow these vertically-aligned nanocomposites that are of interest for magnetic and catalytic applications. These results open up a wide range of new opportunities to design multilayer and nanostructured materials to achieve specific properties that cannot be found in the bulk.

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Sumanta Tewari

The last roadblock to majorana zero modes and topological quantum computation in semiconductor heterostructures

Sumanta Tewari, PHD
Associate Professor of Physics
Department of Physics and Astronomy
Clemson University, Clemson, South Carolina
March 22, 2019
1:00 - 2:00 p.m.
Science Hall W1002

Abstract: With the discovery of topological insulators (TI), studies of topological phases have tremendously accelerated in the last few years. Examples include 3D TI, 2D quantum spin-Hall insulator, topological Dirac and Weyl semimetal, and topological superconductors (TS). In recent years we proposed a semiconductor-superconductor (SM-SC) heterostructure as an excellent candidate for realizing a topological superconductor. Recent experiments on this system have claimed that the long-sought-after Majorana fermions, first proposed in high energy physics in 1929, may have been realized at the interface between this TS system and metallic leads, paving the way for topological quantum computation (TQC). In this talk I will discuss the theory of Majorana fermions and TQC, overview of the current experiments, and our recent work on Andreev bound states in SM-SC heterostructures, illustrating why the claims of experimental success may be hugely encouraging but somewhat premature.



Previous Seminars

2014

2015

2016

2017

2018

 


Seminar series organizers: Dr. Trinanjan Datta (tdatta@augusta.edu), Dr. Christopher Klug (cklug@augusta.edu), Dr. Shaobin Miao (smiao@augusta.edu)

Seminar series sponsored by: Augusta University Research Institute, College of Science and Mathematics, Department of Chemistry and Physics