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Wang, Z. W.

Publications and source records attributed to Wang, Z. W..

Asymptotically safe clockwork mechanism

In this paper, we demonstrate that safe quantum field theories can accommodate the clockwork mechanism upgrading it to a fundamental theory a lá Wilson. Additionally, the clockwork mechanism naturally sources Yukawa hierarchies for safe completions of the Standard Model. As proof of concept, we investigate a safe Pati-Salam clockwork structure.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Directional massless Dirac fermions in a layered van der Waals material with one-dimensional long-range order

One or a few layers of van der Waals (vdW) materials are promising for applications in nanoscale electronics. Established properties include high mobility in graphene, a large direct gap in monolayer MoS 2 , the quantum spin Hall effect in monolayer WTe 2 and so on. These exciting properties arise from electron quantum confinement in the two-dimensional limit. In this work, we use angle-resolved photoemission spectroscopy to reveal directional massless Dirac fermions due to one-dimensional confinement of carriers in the layered vdW material NbSi 0.45 Te 2 . The one-dimensional directional massless Dirac fermions are protected by non-symmorphic symmetry, and emerge from a stripe-like structural modulation with long-range translational symmetry only along the stripe direction as we show using scanning tunnelling microscopy. Our work not only provides a playground for investigating further the properties of directional massless Dirac fermions, but also introduces a unique component with one-dimensional long-range order for engineering nano-electronic devices based on heterostructures of vdW materials.

36 MATERIALS SCIENCE↗