Center for Emergent Materials: an NSF MRSEC

The Center for Emergent Materials engages researchers from multiple disciplines to work in teams on scientific problems too complex for a single researcher to solve. The CEM, established in 2008, is located at The Ohio State University and funded by a National Science Foundation MRSEC award.


Exotic Kitaev interaction is dominant in two-dimensional (2D) ferromagnet CrI3

A collaboration of researchers from three CEM IRGs led by Nandini Trivedi,  Joshua Goldberger and Chris Hammel published a study of the 2D ferromagnet CrIin Physical Review Letters‘ first issue of 2020.

In this study, angle-dependent ferromagnetic resonance (FMR) was combined with theoretical analysis based on crystal symmetries to reveal the fundamental spin interactions in the atomic monolayer ferromagnet CrI3.   The excitement surrounding 2D van der Waals ferromagnets has stimulated great interest in the origins of the magnetism and the magnetic anisotropy that makes ordering possible.  The spin model presented here, constrained by crystal symmetries, and precisely quantified by combining spectroscopic FMR measurements with the value of the ferromagnetic critical temperature, reveals three spin exchange interactions:  Heisenberg , Kitaev, and anisotropic exchange interactions. A remarkable finding is that the Kitaev interaction is much stronger than other interactions in CrI3—exceeding the conventional Heisenberg exchange interaction by a factor of 25.  This surprising result provides clues that could enable the realization of a magnetically frustrated quantum spin liquid arising from Kitaev physics.

The researchers on this work, funded primarily by the CEM, also collaborated with scientists at the National High Magnetic Field Laboratory and the Korea Institute for Advanced Study. The paper can be read on the Physical Review Letters website.

CEM Creates Professional Development Course for Graduate Students

CEM has created a professional development course for STEM graduate students that will launch in Spring 2020. The course will give Ph.D.-seeking students the opportunity to develop skills in resume and CV writing, job searching, interviewing, and salary negotiation, to name a few. Students will network and interact with professionals from across the Ohio State campus to develop their skills and deepen their understanding of how to manage their professional and personal lives in diverse settings.

The Graduate Student Professional Development Course (PHYS 7891) takes place on Thursdays from 10:30-11:30, starting January 9, 2020. The course instructors are CEM Director P. Chris Hammel and CEM Outreach and Inclusion Director Michelle McCombs.

More information about the course can be found on the class’ website. A syllabus can be found here.