Magneto-chiral spectroscopy of two-dimensional crystals

Two-dimensional (2D) crystals exhibit unusual optical and electronic properties that can be exploited for novel optoelectronic applications [1]. The family of 2D materials grows day by day, hugely expanding the scope of possible phenomena to be explored in two dimensions, as well as the possible van der Waals (vdW) heterostructures that one can create. Until recently, this family has been missing one crucial member: 2D magnets. The situation has changed over the past two years with the introduction of a variety of atomically thin magnetic crystals, which unraveled a new class of the vdW heterostructures, offering new perspectives in this rapidly expanding field. Rapid progress, particularly in the growth area, is beginning to enable ways to implement 2D crystals into devices with tailored functionalities.

Recently, the helicity-resolved Raman spectroscopy was found to be an effective tool to directly probe the ferromagnetism in 2D magnets [3]. Circularly polarized light carries spin angular momentum, which makes the helicity-resolved Raman scattering to be sensitive to the electronic spin configuration in magnetic materials. Besides the lattice excitations and quasielastic scattering in the paramagnetic regime, magnon scattering and the spin-wave gap can be explored in the magnetically ordered state.

We seek a PhD student to work with the advisor on the magneto-optical spectroscopies under extreme conditions (low-temperatures & high magnetic fields) on vdW heterostructures build from 2D magnets. The goal is to understand the complex light-matter interaction in the new class of nanomaterials with unique magneto-optical properties.

References:
[1] G. Eda & S.A. Maier, ACS Nano 2013, 7, 7, 5660–5665
[2] A. Gibertini et al, Nature Nanotechnology 2019, 14, 408–419
[3] B.B. Lyu et al, Nano Letters 2020, 8, 6024-6031