Collaborative Research: Nonreciprocal Transport in Hybrid Chiral Crystals

Nontechnical description Symmetry can be found everywhere in nature. From the spherical symmetry of a hydrogen atom to the spiral arms of the Milky Way galaxy, symmetry is seen at length scales from the atomic to the galactic. Inversion symmetry, where every point in a crystal can be mirrored through a central point, gives rise to striking optical and electrical properties in semiconductors. This project investigates the unusual properties of a class of symmetry-breaking materials known as chiral crystals. Understanding their behavior provides a foundation for discovery at the forefront of materials physics. These materials could also enable unconventional functionalities useful for quantum sensing, telecommunications, and advanced computing. Beyond the laboratory, this project integrates scientific discovery with a comprehensive educational mission designed to prepare a skilled STEM workforce. The research team develops new courses, hosts hands-on bootcamps for undergraduate students, and leads public outreach. Through these activities, students and the public gain a deeper appreciation for the basic sciences that drive technological innovation. Technical description This project addresses the scientific problem of understanding and controlling nonreciprocal transport in noncentrosymmetric chiral crystals. Progress in this field has been hindered by the limited availability of suitable materials, as most inorganic crystals are achiral. The research team tackles this challenge by designing and investigating symmetry-breaking, chiral crystals based on two-dimensional hybrid metal halides. These semiconducting materials features alternating organic and inorganic layers. The chemical diversity and low crystal dimensionality provide an ideal platform for manipulating inversion symmetry and systematic studying of the relationship between crystal structure and nonreciprocal transport. The research employs an iterative approach, integrating materials design, chemical synthesis, physical property characterization, and microscopic modeling. This closed feedback loop ensures a rational foundation for discovering and designing new materials with programmable symmetry and tailored nonreciprocal transport behaviors. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2530253 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Letian Dou | Institution: Emory University, ATLANTA, GA | Award Amount: $200,000 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2530253 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2530253.html