Synthesis and characterization of nanostructured topological materials

Abstract

As a branch of quantum materials, topological materials are noted for their topologically nontrivial band structures, massless Dirac or Weyl fermions, strong spin-orbit coupling, and boundary-protected states, endowed with exotic physical properties totally different from those of conventional insulators and metals. In this era of information intelligence, topological materials with unconventional properties have drawn increasing attention, with the growing demand for high-performance electronics, spintronics, optoelectronics, thermoelectrics, etc. Besides, compared to bulk forms, nanostructured topological materials are more compatible with electronic and optoelectronic applications in terms of device integration and fabrication. They also possess enhanced contributions from surface/edge states and geometry-regulated band structures. Therefore, there is a demand for manufacturing and studying nanostructured topological materials. With this motivation, recently there have been burgeoning explorations of nanostructured topological materials. In this review, we systematically summarize the exciting proceedings in both synthesis and characterizations of nanostructured topological materials. We start from the introduction of state-of-the-art synthesis methods, as well as their capability of structural control, feasibility, and potential for scaling up. Then, we summarize the characterization tools and the corresponding properties of nanostructured topological materials, in which the origins of these topologically-related physical properties and their nanostructure dependences are elaborated. Perspectives on the challenges and opportunities are also given in the final part to summarize the advances and propose possible directions in the field of nanostructured topological materials.