Online seminar by Prof. Riccardo Comin (MIT)

A type-II multiferroic in two dimensions

On February 17th  2022 at 3:00 p.m. (CET) the following on-line seminar will be given by Riccardo Comin (home page) from Massachusetts Institute of Technology (MIT), Cambridge, USA.

Abstract

In this talk, I will present our recent study and realization of type-II multiferroic order in a single atomic layer of the transition metal-based van der Waals material NiI2. The multiferroic state of NiI2 is characterized by an inversion-symmetry-breaking helimagnetic order which induces a chirality-dependent electrical polarization. Using circular dichroic Raman measurements, we directly probed the magneto-chiral ground state and its electromagnon modes originating from dynamic magnetoelectric coupling. Using birefringence and second-harmonic generation measurements, we observed a highly anisotropic electronic state simultaneously breaking three-fold rotational and inversion symmetry to support polar order. The evolution of the optical signatures as a function of temperature and layer number surprisingly revealed an ordered magnetic, polar state that persists down to the ultrathin limit of monolayer NiI2.

Details of the online seminar

Use the following info to connect to the seminar on Zoom

Meeting ID: 894 9431 8028
Link: https://polimi-it.zoom.us/j/89494318028

For any technical issue, please promptly contact christian.rinaldi@polimi.it

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