High-field magnetotransport and Fermi surface topology of the quasi-1D transition metal tetrachalcogenide TaTe4

Following the discovery of the quantum Hall effect, the exploration for new materials and subsequent identification of new phases, later appointed as ‘topological’, was initiated. This search has led to the discovery of exotic electronic phases with significant implications across various applications. The most notable examples include topological insulators, topological superconductors, Weyl semimetals and others. Furthermore, new families of materials have been postulated as potential candidates to host these new states, such as the transition metal tetrachalcogenides (TMTCs) . Due to their low dimensionality, these materials are prone to Peierls instabilities, leading to the ground state being described by a charge density wave (CDW) collective phase. Topological phases can coexist with a CDW and in this coexistence, the emergence of even more interesting new electronic states, such as axionic states, is predicted. In this work we focus on the TMTC compound TaTe₄ which hosts a CDW phase at room temperature and below, and it is also a candidate for being a Weyl semimetal, therefore being aperfect playground to study the coexistence between topological states and electronically correlated states. To study this, we performed high field (B < 35 T) magnetotransport measurements to reconstruct the Fermi surface of the material through the angle- and temperature dependence of Shubnikov de Haas (SdH) oscillations, as well as high-field current-voltaje curvesOur results show higher resolution than previous reports, as well as features that reveal the non-trivial topology of the band structure of this material.