Resume

Hello! I’m Chinedu Ekuma, PhD. My research focuses on computer-aided design and simulations to understand the fundamental origin of the complex behaviours in materials.

  • Residence: USA
  • PhD Supervision: Available
  • Address: 16 Memorial Drive East Bethlehem, PA 18015
  • Phone: +1 (610)-758-6428
  • E-mail: che218@lehigh.edu
Research Areas
DEFECTS IN 2D MATERIALS
Defects in materials are ubiquitous and at the nanoscale quantum effects, the impact is more pronounced, which could have a significant impact on device performance. At a high density of defect states, in a material with potential applications as a quantum transistor, intermediate band solar cells, etc. support the development of any practical applications, we need to develop a better understanding of the properties of disordered 2D materials and their hybrid structures. We use state-of-the-art techniques ranging from approaches in density functional theory to first-principles-based many-body model Hamiltonians to explore diverse arrays of materials.
INSULATORS & SEMICONDUCTORS
The electronic property of a material is the most essential since it serves as the input in diverse material characterization. Hence, their accurate determination is paramount to the predictive capabilities of any computational approach. For insulators and semiconductors (I&S), any predicted property depends sensitively on the energy, which is the difference in energy between the highest occupied states (homo for molecules) and lowest unoccupied states ( for molecules). Determining unambiguously is crucial for actual device applications. For reliability and predictability, with a minimalistic parameter. We use state-of-the-art computational approaches to study diverse I&S for applications not limited to high power, solar cells, photodetectors, and light emitters, etc.
HYBRID MATERIALS
At the heart of modern devices are heterostructures, which is the stacking of thin films of at least two different materials to form a hybrid structure. The state-of-the-art heterostructure-based devices often involve stacks of few nanometer thick crystals. However, the ultimate limit would be a hitherto single-atomic-layer structure. We are interested in exploring and using low-dimensional hybrid structures in a range of applications such as thermoelectricity, Photovoltaics and Solar cells, hydrogen evolution from water using sunlight and semiconductor, and quantum transistors.
NANOMATERIALS
At the nanoscale, materials exhibit superior electrical, optical, transport, and mechanical properties distinct from their macroscale aggregates. In our research, we computationally explore these unique properties to design electronic materials with new functionalities, e.g. exciton transport and ultra-strong van Waals. Instead of trying to reduce a bulk material to the atomic scale, these class of materials referred to as two-dimensional materials 2DMs are already in the atomic limit. The successful isolation of graphene, a stable 2D monolayer of graphite, heralded the discovery of many other 2D materials. At present, to form a 2DMs. We are interested in exploring their novel properties for applications in nanoelectronic and devices.
INTERCALATION IN LAYERED MATERIALS
Chemical or electrical doping is one of the efficient ways of improving and controlling carrier transport, density, and charge injection in materials. One of such means of achieving this is via intercalation. For example, intercalating Li into layered transition metal dichalcogenides (TMDs) have been for battery applications. in a variety of such systems and are exploring various organometallic molecules, e.g., metallocene as possible to tune the properties of TMDs. Initial first-principles calculations reveal that the electronic properties of vertically stacked 2D TMDs, e.g. HfS2 could be tune with intercalating, which behaves like pseudo-alkali metals, transferring electrons to the characterized by a shift of the Fermi level towards the empty states and an increase of the current density. The process of evolving in the vertically stacked van Waals that led to the doping is charge transfer from the to the host material. We are exploring other systems.
EFFECTIVE HAMILTONIAN FOR REAL MATERIALS
The description of real materials using dynamical mean-field approximation (DMFA)-based approaches need realistic lattice and electronic structures, including interaction parameters. Since the dominant many-particle effects are local or short-range, the first-principles electronic structure needs to unto a basis set of local orbitals. via, which involves integrating out mainly the high-energy scales or focusing on the energy window of interest by constructing Wannier functions. as. In the electronic structure of a is mapped unto the Brillouin of the original cell to an effective disordered Hamiltonian. Sometimes, we are also interested in the effects of Coulomb interactions. There few ways to achieve this: 1) account for the effects of electron correlations via Hubbard interactions parameter; 2) self-consistently account for the many-body effects in the effective Hamiltonian by unfolding or a converged Green's function and screened Coulomb interactions (GW) calculations; and 3) construct an energy-dependent Anderson-Hubbard Hamiltonian. The last approach seems more natural and computationally efficient. It involves carrying out an independent GW calculation, e.g., self-consistent quasiparticle GW method for the parent material to a material-specific dynamical, screened electron-electron interaction.
Experience
2019-present
Assistant Professor, Department of Physics, Lehigh University, Bethlehem, PA
• Student mentoring, teaching graduate and undergraduate students • Algorithm and code development for studying correlated systems • First-principles study of diverse materials including nanostructures and interfaces
2018
George F. Adams Distinguished Research Fellow, U.S. Army Research Lab., Adelphi, MD
• Development and application of many-body approaches to design and discover technologically relevant low-dimensional materials. • First-principles study of surfaces and interfaces.
2015-2017
Research Fellow, National Research Council, the National Academies, U.S. Naval Research Lab., Washington, DC
• Initiated and developed a first-principles Typical Medium Dynamical Cluster Approximation plus density functional theory (TMDCA@DFT), which is a mean-field approach with an intrinsic order parameter for the proper characterization of electron localization in materials. • Demonstrated expertise in first-principles, many-body study of low-dimensional materials. • Initiated ideas for algorithm and code development to study correlated materials.
Education
May 2015
Ph.D. Computational Condensed Matter and Materials Physics
Louisiana State University, Baton Rouge, LA, USA • Dissertation: “Towards the Realization of Systematic, Self-Consistent Typical Medium Theory for Interacting Disordered System.” • Committee: Profs. Mark J
July 2010
M.Sc. Computational Physics
Southern University and A&M College, Baton Rouge, LA, USA • Thesis: “Correct Density Functional Theory Description of Electronic Properties of CdS and FerroNaNO2.” • Advisors: Profs. Diola Bagayoko and Jin Tong Wang.
June 2009
M.Sc. Theoretical Physics
University of Nigeria, Nigeria • Thesis: “Thermodynamics of Continuous Phase Transition.” • Advisors: Profs. C. M. I. Okoye and G. C. Asomba.
Jan. 2007
B.Sc. (Summa Cum Laude) Industrial Physics
Ebonyi State University, Nigeria • Thesis: “Effects of Zinc Addition on the Corrosion Susceptibility of Aluminum Alloy in Selected Media Concentration.” • Advisor: Prof. N. E. Idenyi.
Our Team
Research Opening Available

Several openings are available for highly motivated individuals (students and postdocs) with an interest in materials modelling and in developing tools for computational condensed matter and materials physics. Interested applicants should send their CV to che218@lehigh.edu

Information for graduate students can be found at Physics@Lehigh