Novel 2D Materials

The library of 2D materials is rapidly expanding. Beyond graphene and conventional 2D semiconductors, novel 2D materials with unprecedented quantum material properties have recently attracted immense research interest. Well-known examples include WTe₂, which is a Quantum Spin Hall insulator and exhibits gate-induced superconductivity down to the monolayer limit, whereas in its bulk form, it is a type-II Weyl semimetal; few-layer NbSe₂ with an odd number of layers, where Ising spin-orbit coupling (SOC) resulting from broken inversion symmetry stabilizes the superconducting state against in-plane magnetic fields far exceeding the Pauli paramagnetic limit; and so on. These novel 2D materials are known to be chemically reactive. Employing an environmentally controlled van der Waals characterization and assembly line built inside a state-of-the-art glovebox system, we fabricate homo- and heterostructures of novel ferroelectric, ferromagnetic, semiconducting, superconducting, and topological 2D materials, and investigate novel emergent quantum material phenomena towards novel quantum material systems with tunable order parameters and nontrivial topology. 

Two-fold symmetric superconductivity in few-layer NbSe2

Observe two-fold symmetric superconductivity in few-layer NbSe₂, revealing unconventional pairing mechanisms enabled by reduced dimensionality.

Alex Hamill*, Brett Heischmidt*, Egon Sohn, Daniel Shaffer, Kan-Ting Tsai, Xi Zhang, Xiaoxiang Xi, Alexey Suslov, Helmuth Berger, László Forró, Fiona J. Burnell, Jie Shan, Kin Fai Mak, Rafael M. Fernandes, Ke Wang* & Vlad S. Pribiag*, Nat. Phys. 17, 949-954 (2021)