Joint research project led by the University of Augsburg and the Technical University of Munich with the participation of eight universities and research institutes.
Collaborative Research Center Transregio TRR360,
Constrained Quantum Matter, for the development and investigation of novel materials whose properties are significantly influenced by quantum effects.
In-plane and out-of-plane optical response of the nodal-line semimetals ZrGeS and ZrGeSe
Polarization-dependent reflectivity measurements were carried out over a broad frequency range on single-crystalline ZrGeSe and ZrGeS compounds, which are closely related to the prototype nodal-line semimetal ZrSiS. These measurements revealed the strongly anisotropic character of both ZrGeSe and ZrGeS, with a reduced plasma frequency for the out-of-plane direction E∥c as compared with the in-plane direction E∥ab.
Pressure-induced excitations in the out-of-plane optical response of the nodal-line semimetal ZrSiS
The anisotropic optical response of the layered, nodal-line semimetal ZrSiS was investigated for the first time by frequency-dependent reflectivity measurements for the polarization along and perpendicular to the layers. Under external pressure, two prominent excitations appear in the out-of-plane optical conductivity, which are discussed in the context of the recently proposed excitonic insulator phase in ZrSiS.