Research
Overview The Yang group's research interests are in the areas of computational materials science, with particular emphasis on materials modeling and simulation using first-principles (or ab-initio) calculations. A theme of our research is to study structural, electronic, optical and magnetic properties of materials, aiming to understand, optimize, and predict materials properties for the design of novel functional nanomaterials. Collaborations with both theorists and experimentalists are welcome. Please contact me directly if you are interested.
Major Research Projects In Progress 1. Computational Design of Perovskite-Based Functional/Structural Materials Our current research focuses on the electronic structure characterization and materials design of perovskites-based functional nanomaterials, with the support of the perovskite-oriented quantum materials database that is produced using the automatic framework AFLOW. i) Perovskite-Based Functional Materials for Electron Transport Our Related Publications: Appl. Phys. Lett. 105, 141602 (2014); ACS Appl. Mater. Interfaces, 6, 22351-22358, (2014); J. Appl. Phys., 117, 115305 (2015); RSC Adv. 5, 15682-15689, (2015); ACS Appl. Mater. Interfaces, 7, 5305–5311, (2015); ACS Appl. Mater. Interfaces, 7, 14294-14302, (2015); Yang Yang Yang ii) First-Principles Thermodynamics of Perovskite-Based Interface and Grain Boundary Our Related Publications: J. Appl. Phys., 117, 175101, (2015); J. Appl. Phys., 117, 115305 (2015); ACS Appl. Mater. Interfaces, 7, 14294-14302, (2015); Phys. Chem. Chem. Phys. (DOI:10.1039/C5CP05100B) Yang Yang iii) Perovskite-Based Functional Materials for Energy Conversion Our Related Publications: J. Phys. Chem. C, 118, 24383-24388, (2014); Phys. Chem. Chem. Phys. 18, 857, (2016); ACS Catalysis, 6, 1097, (2016) Yang Yang Yang Yang 2. Atomistic Understanding of MoS2-Based Two-Dimensional Materials for Hydrodesulfurization
Computational Understanding and Manipulation of Advanced Functional Materials We are interested in studying structural, electronic, optical and magnetic properties of materials from first-principles electronic structure calculations. Starting by understanding/manipulating materials properties through computer simulations, our primary aim is to help design novel functional materials with various applications from production, storage and conversion of energy to electronic information technology. We would like to collaborate with experimentalists and work together to explore unknown phenomena in every aspect of materials research, particularly in the fields of energy materials and spintronics. Please contact me if you are interested! Yang Yang
High-throughput (HT) Computational Materials Design HT computational materials design provides us a way to realize a rapid discovery of novel functional materials. With the development of computer hardware and availability of high-performance software for first-principles electronic structure calculations, it is becoming practical to produce a huge quantum materials repository. The key idea behind the HT computational materials design is to find a reliable and accessible descriptor, which can help us identify the candidates of desired materials. For example, in a recent study, Dr. Yang carried out a HT search of topological insulators (TI) based on the materials database, AFLOWLIB.org. Dr. Yang and colleagues defined the 'SOC-noSOC energy discrepancy', the energy gap difference between spin-orbit coupling (SOC) and noSOC calculations as a function of cell dimensions, which is calculated at time-reversal-invariant momentum (TRIM) points. They found that 'SOC-noSOC energy discrepancy' varies much less than energy gaps calculated by SOC and noSOC calculations. On the basis of this discovery, Dr. Yang and colleagues introduced a variational 'high-throughput TI robustness descriptor'. Having this HT descriptor, the critical lattice inducing topological phase transition can be automatically estimated. They examined the whole AFLOWLIB.org database, and rapidly identified 28 novel potential TIs in five different symmetry families. [Nat. Mater. 11(7), 614-619, (2012)]. Yang
Developing HT Computational and Data-analysis Infrastructures To search for materials with desired properties using HT method, besides automatic electronic structure calculations for hundreds of thousands of compounds, a systemic characterization of basic material properties is necessary. For instance, as one co-developer of the AFLOW consortium, Dr. Yang developed high-throughput programs for electronic structures analysis. These programs can generate the electronic band structures, density of states (DOS), and the projected-DOS plots automatically. They have been successfully applied to visualize the electronic band structures of over 30,000 compounds in AFLOWLIB.org. Yang Yang