Monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>MnBi</mml:mi> <mml:mn>2</mml:mn> </mml:msub> <mml:msub> <mml:mi>Te</mml:mi> <mml:mn>4</mml:mn> </mml:msub> </mml:mrow> </mml:math> : Atomic-scale insigh

As the first intrinsic antiferromagnetic topological insulator, ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ offers a platform for investigating topological phenomena driven by magnetism. Prior studies focused on bulk single crystals and exfoliated flakes, but the extreme two-dimensional (2D) limit remains underexplored, despite theoretical predictions of exotic behavior. In particular, synthesis and atomic-scale characterization of ultrathin ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ films remain challenging. Here we explore molecular beam epitaxy grown ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ thin films down to a single-layer thickness. Structural characterization via electron and x-ray diffraction, atomic force microscopy, and scanning tunneling microscopy confirms layer-by-layer growth and high crystallinity, while magnetotransport measurements show the expected magnetic signatures. Interestingly, scanning tunneling microscopy and quasiparticle interference imaging reveal Dirac-like surface states that persist even in monolayer films and monolayer islands. Our experiments provide elusive atomic-scale insights into the band structure of ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ in the 2D limit and under lateral confinement, and establish a foundation for the synthesis of heterostructures based on monolayer ${\mathrm{MnBi}}_{2}{\mathrm{Te}}_{4}$ and device applications.