Title: Sub-Nanometer Channels Embedded in Two-Dimensional Materials,
Abstract: Two-dimensional (2D) materials are among the most promising candidates for
next-generation electronics due to their atomic thinness, allowing for flexible
transparent electronics and ultimate length scaling. Thus far, atomically-thin
p-n junctions, metal-semiconductor contacts, and metal-insulator barriers have
been demonstrated. While 2D materials achieve the thinnest possible devices,
precise nanoscale control over the lateral dimensions is also necessary. Here,
we report the direct synthesis of sub-nanometer-wide 1D MoS2 channels embedded
within WSe2 monolayers, using a dislocation-catalyzed approach. The 1D channels
have edges free of misfit dislocations and dangling bonds, forming a coherent
interface with the embedding 2D matrix. Periodic dislocation arrays produce 2D
superlattices of coherent MoS2 1D channels in WSe2. Using molecular dynamics
simulations, we have identified other combinations of 2D materials where 1D
channels can also be formed. The electronic band structure of these 1D channels
offer the promise of carrier confinement in a direct-gap material and charge
separation needed to access the ultimate length scales necessary for future
electronic applications.