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It was demonstrated recently that the nano-optical and nanoelectronic properties of VO₂can be spatially programmed through the local injection of oxygen vacancies by atomic force microscope writing. In this work, we study the dynamic evolution of the patterned domain structures as a function of the oxygen vacancy concentration and the time. A threshold doping level is identified that is critical for both the metal–insulator transition and the defect stabilization. The diffusion of oxygen vacancies in the monoclinic phase is also characterized, which is directly responsible for the short lifetimes of sub-100 nm domain structures. This information is imperative for the development of oxide nanoelectronics through defect manipulations.

Controlling material properties at the nanoscale is a critical enabler of high performance electronic and photonic devices. A prototypical material example is VO₂, where a structural phase transition in correlation with dramatic changes in resistivity, optical response, and thermal properties demonstrates particular technological importance. While the phase transition in VO₂can be controlled at macroscopic scales, reliable and reversible nanoscale control of the material phases has remained elusive. Here, reconfigurable nanoscale manipulations of VO₂from the pristine monoclinic semiconducting phase to either a stable monoclinic metallic phase, a metastable rutile metallic phase, or a layered insulating phase using an atomic force microscope is demonstrated at room temperature. The capability to directly write and erase arbitrary 2D patterns of different material phases with distinct optical and electrical properties builds a solid foundation for future reprogrammable multifunctional device engineering.

Driven by an ever‐expanding interest in new material systems with new functionality, the growth of atomic‐scale electronic materials by molecular beam epitaxy (MBE) has evolved continuously since the 1950s. Here, a new MBE technique calledhybrid‐MBE (hMBE) is reviewed that has been proven a powerful approach for tackling the challenge of growing high‐quality, multicomponent complex oxides, specifically theABO₃perovskites. The goal of this work is to (1) discuss the development ofhMBE in a historical context, (2) review the advantageous surface kinetics and chemistry that enable the self‐regulated growth ofABO₃perovskites, (3) layout the key components and technical challenges associated withhMBE, (4) review the status of the field and the materials that have been successfully grown byhMBE which demonstrate its general applicability, and (5) discuss the future ofhMBE in regards to technical innovations and expansion into new material classes, which are aimed at expanding into industrial realm and at tackling new scientific endeavors.