College of Arts and Sciences

Designing materials: a synergistic process between theory, experiment and belief

Aldo Romero, Dept. of Physics and Atronomy, West Virginia University, Morgantown

The scientific process of designing materials has changed in the last ten years, as now theoretical methods have advanced to the level of becoming predictive, materials databases are increasing in size and experiments are more accurate and detailed. In this synergistic path, methods that combine all these methodologies are ideal, as long as we manage to condense the necessary design details into a series of fundamental material parameters. In this talk, I will discuss the atomistic process to design materials from scratch by using theoretical methods only based on the chemical composition and with little knowledge on the desired material or property of interest.

Continue reading… Aldo Romero, West Virginia University, Designing materials: a synergistic process between theory, experiment and belief

Strong fluctuations in the relaxation of a 2D granular fluid

Horacio Castillo, Department of Physics and Astronomy, Ohio University

Glass transitions are associated with a rapid increase of the
relaxation time in a system as a function of an external parameter,
usually temperature or volume fraction. In the regime near the glass
transition, materials exhibit “dynamical heterogeneity”, i.e., the
presence of correlated fluctuations in the dynamical behavior of small
regions of the system, whose origin is still poorly understood. I will
discuss the results of large-scale numerical simulations of a two
dimensional granular fluid,

Continue reading… Horacio Castillo, Ohio University, Strong fluctuations in the relaxation of a 2D granular fluid

Geometrically Frustrated Coulomb Liquids
V. Dobrosavljevic
Department of Physics and National High Magnetic Field Laboratory
Florida State University, Tallahassee, Florida 32306, USA

We show[1] that introducing long-range Coulomb interactions immediately lifts the massive
ground state degeneracy induced by geometric frustration for electrons on quarter-filled
triangular lattices in the classical limit. Important consequences include the stabilization of
a stripe-ordered crystalline (global) ground state, but also the emergence of very many lowlying
metastable states with amorphous “stripe-glass” spatial structures[2]. Melting of the
stripe order thus leads to a frustrated Coulomb liquid at intermediate temperatures,

Continue reading… Vladimir Dobrosavljevic, Florida State University, Geometrically Frustrated Coulomb Liquids

Controlled Synthesis and Emergent Properties of Heavy Transition Metal Oxides and Sulfides

Shixiong Zhang

Department of Physics, Indiana University, Bloomington, IN, USA

Heavy transition metal compounds (e.g. oxides and sulfides) often possess strong spin-orbit coupling (SOC) because of their high atomic numbers and electron correlation due to their compact d-orbitals. The competition and interplay of SOC and electron interactions is believed to induce a variety of novel electronic and magnetic ground states. In this talk, I will present our recent experimental work on two representative material systems, namely iridates and layered metal sulfides which exhibit a broad spectrum of intriguing physical properties.

Continue reading… Shixiong Zhang, Indiana University, Controlled Synthesis and Emergent Properties of Heavy Transition Metal Oxides and Sulfides

From Giant Magnetoresistance to Nonlinear Magnetoresistance in Quantum Materials – An Exciting Journey with Spin

Shulei Zhang

Condensed Matter Theory Group, Materials Science Division, Argonne National Laboratory

Abstract:

Ever since its surprising emergence from relativistic quantum mechanics, spin has been known as an intrinsic angular momentum that plays a crucial role in electronic structure of matter. When the flows of spin and charge become intertwined through spin-orbit coupling or nontrivial magnetic structures, a host of intriguing magnetotransport phenomena emerge, such as giant magnetoresistance, spin Hall, topological Hall etc.

Continue reading… Shulei Zhang, Argonne National Laboratory, From Giant Magnetoresistance to Nonlinear Magnetoresistance in Quantum Materials – An Exciting Journey with Spin

Functional quantum materials, including Mott insulators and high temperature superconductors, are at the forefront of modern materials science and condensed matter physics research. These materials are being actively explored for transformative technological applications, including efficient energy generation, storage and transmission. Understanding the fundamental mechanisms behind the exotic phases of matter emerging in quantum materials is a grand challenge, which must be overcome to maximize technological advancement.

            Due to the complexity of the many-electron problem, analytic theories become often unreliable and numerical treatment is required. Over the past decades, numerical analysis has become a very powerful tool for studying strongly correlated electron systems.

Continue reading… Hanna Terletska, Middle Tennessee State University,Understanding quantum materials using computational methods.

In this talk I will discuss how synthetic photonic materials can be utilized to explore several non-Hermitian symmetries and their topological implications. Although difficult to access in high-energy physics and conventional condensed matter systems, these non-Hermitian symmetries can be realized in photonic materials with carefully arranged gain and loss elements. Therefore, such synthetic photonic materials provide an ideal platform to explore the ramification of these symmetries, including parity-time (PT) symmetry and non-Hermitian particle-hole symmetry, as well as the resulting novel optical phenomena and functionalities.

PT symmetric photonics [1] is one of the fastest growing fields in the past five years.

Continue reading… Li Ge, City University of New York, Exploring non-Hermitian symmetries and topology using synthetic photonic materials