Admal wins prestigious CAREER Award

MechSE Assistant Professor Nikhil Chandra Admal has won a prestigious NSF CAREER Award. The National Science Foundation Faculty Early Career Development Program (CAREER) award is given to tenure-track faculty whose research work demonstrates great potential during the first five years of their career. Admal’s CAREER proposal is titled, “Bicrystallography-informed mechanics of two-dimensional materials.”

“Our research group works at the interface of mechanics, materials science, and mathematics to understand the complex mechanisms — starting from the atomic scale to the continuum scale — behind plastic deformation of crystal interfaces,” Admal said. With a PhD in aerospace engineering and mechanics, his postdoctoral work focused on grain boundaries (GB) in material science.

Admal’s desire to study material science problems from a mechanics perspective moved him to focus on GBs. Many ideas in his CAREER proposal on 2D materials originate from his work on GB plasticity and bicrystallography applied to GBs. Two-dimensional materials (e.g. graphene), which consist of a single or a few layers of atoms, manifest exotic physical properties due to the presence of strong electronic correlations. In recent years, 2D heterostructures, which consist of stacks of 2D materials, have emerged as an important class of quantum materials. The weak van der Waals (vdW) interactions at the heterointerfaces of 2D lattices in such materials offer high fidelity in tuning the local atomic environment, thus allowing exquisite control over the quantum properties of such systems. 

A fundamental feature that dictates the structural response of a heterointerface is the degree of incommensurability (lacking a basis of comparison) between the two 2D materials. The incommensurability leads to the formation of defects called interface dislocations. The objective of Admal’s research is to characterize the response of heterointerfaces to temperature, shear, and normal forces in terms of interface dislocations. Doing so could lead to a new understanding of how structural properties emerge from vdW interactions, which in turn will pave the way for a systematic design and large-scale synthesis of heterostructures. This is foundational for exploring strain engineering as a design tool for 2D materials systems. 

“This award reflects my vision that transformative ideas can emerge at the interface of diverse research arenas,” he said.

The applications of this research are broad. For example, superconductivity emerges when a bilayer of graphene is subjected to a small twist. Two-dimensional heterostructures also demonstrate outstanding mechanical properties such as superlubricity and high strain tolerance, which leads to emergent technologies related to nanoelectronics and quantum information science.

In his related outreach efforts as part of the CAREER funding, Admal hopes to continue working with high school students through the Worldwide Youth in Science and Engineering (WYSE) program. He plans to collaborate with high school teachers in creating STEAM activities, which include working with Moiré lattices from an artistic viewpoint.