Université de Fribourg

Optical conductivity of the type-II Weyl semimetal TaIrTe4

Mardelé, F. Le ; Santos-Cottin, D. ; Martino, E. ; Semeniuk, K. ; David, S. Ben ; Orbanić, F. ; Novak, Mark ; Rukelj, Z. ; Homes, C. C. ; Akrap, Ana

In: Physical Review B, 2020, vol. 102, no. 4, p. 045201

TaIrTe4 is an example of a candidate Weyl type-II semimetal with a minimal possible number of Weyl nodes. Four nodes are reported to exist in a single plane in k space. The existence of a conical dispersion linked toWeyl nodes has yet to be shown experimentally. Here, we use optical spectroscopy as a probe of the band structure on a low-energy scale. Studying optical conductivity allows us to...

Université de Fribourg

Preferential out-of-plane conduction and quasi-one-dimensional electronic states in layered 1T-TaS 2

Martino, E. ; Pisoni, A. ; Ćirić, L. ; Arakcheeva, A. ; Berger, H. ; Akrap, Ana ; Putzke, C. ; Moll, P. J. W. ; Batistić, I. ; Tutiš, E. ; Forró, László ; Semeniuk, K.

In: npj 2D Materials and Applications, 2020, vol. 4, no. 1, p. 1–9

Layered transition metal dichalcogenides (TMDs) are commonly classified as quasi-two-dimensional materials, meaning that their electronic structure closely resembles that of an individual layer, which results in resistivity anisotropies reaching thousands. Here, we show that this rule does not hold for 1T-TaS2—a compound with the richest phase diagram among TMDs. Although the onset of ...