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The availability of an ever‐expanding portfolio of 2D materials with rich internal degrees of freedom (spin, excitonic, valley, sublattice, and layer pseudospin) together with the unique ability to tailor heterostructures made layer by layer in a precisely chosen stacking sequence and relative crystallographic alignments, offers an unprecedented platform for realizing materials by design. However, the breadth of multi‐dimensional parameter space and massive data sets involved is emblematic of complex, resource‐intensive experimentation, which not only challenges the current state of the art but also renders exhaustive sampling untenable. To this end, machine learning, a very powerful data‐driven approach and subset of artificial intelligence, is a potential game‐changer, enabling a cheaper – yet more efficient – alternative to traditional computational strategies. It is also a new paradigm for autonomous experimentation for accelerated discovery and machine‐assisted design of functional 2D materials and heterostructures. Here, the study reviews the recent progress and challenges of such endeavors, and highlight various emerging opportunities in this frontier research area. [ABSTRACT FROM AUTHOR]

Advances in research of magnetic two-dimensional van der Waals (2D vdW) materials have opened up new opportunities in miniaturization of spintronic devices at the atomically thin limit. One major research thrust, which is the subject of this review, is that the magnetism of 2D vdW materials and their derived hetero-interface may be significantly affected by the local atomic geometry and environment. As a result, there is a pressing need for powerful advanced technique to characterize magnetic vdW surface and interface. Circularly polarized X-rays from synchrotron radiation light sources are key to this endeavor, as they can probe the microscopic magnetism of a specific element, for their atomic sensitivity, element-specificity, core-level excitation as well as capability of separation for the spin and orbit moments. We review a series of representative experimental achievements, exploiting circularly polarized X-rays, in (1) 2D vdW magnet, (2) magnetic metal/vdW interface, (3) molecule/vdW interface as well as (4) vdW/2D interface. On the basis of the review, advantages of probing magnetic vdW surface and interface by circularly polarized X-rays are presented, and challenges and opportunities are also discussed. [ABSTRACT FROM AUTHOR]