Topological insulators represent a fascinating class of electronic materials with distinctive characteristics. They possess a bulk band gap akin to ordinary insulators while harboring protected conducting states along their edges or surfaces. This unique behavior arises from the interplay of spin-orbit interactions and time-reversal symmetry. In the realm of two-dimensional materials, the quantum spin Hall insulator (QSHI) stands out as a close relative to the integer quantum Hall state.
This thesis delves into the intricate world of topological properties in monolayer 1T’WTe2, a prominent QSHI material. The investigation encompasses various aspects, including the observation of one-dimensional electron flow at the edges of WTe2, explicable through the Tomonaga Luttinger liquid (TLL) theory. Furthermore, the study extends to the domain of topological superconductivity in WTe2. When coupled with a conventional superconductor such as 2H-NbSe2, this material reveals a topological superconducting edge that holds promise for generating Majorana fermions—vital entities in quantum computing applications.
Intriguingly, this thesis goes beyond conventional boundaries to explore a novel phase of topological material: the topological excitonic insulator (TEI) in WTe2. This exploration illuminates the rich and multifaceted nature of topological materials, paving the way for exciting developments in both fundamental physics and practical applications.

References:
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