  Wurtzite ferroelectrics possess transformative potential for next-generation
microelectronics. A comprehensive understanding of their ferroelectric
properties and domain energetics is crucial for tailoring their ferroelectric
characteristics and exploiting their functional properties in practical
devices. Despite burgeoning interest, the exact configurations, and electronic
structures of the domain walls in wurtzite ferroelectrics remain elusive. In
this work, we elucidate the atomic configurations and electronic properties of
electric-field-induced domain walls in ferroelectric ScGaN. By combining
transmission electron microscopy and theoretical calculations, a novel charged
domain wall with a buckled two-dimensional hexagonal phase is revealed. The
dangling bonds associated with these domain walls give rise to unprecedented
metallic-like mid-gap states within the forbidden band. Quantitative analysis
further unveils a universal charge-compensation mechanism stabilizing antipolar
domain walls in ferroelectric materials, wherein the polarization discontinuity
at the 180{\deg} domain wall is compensated by the dangling bond electrons.
Furthermore, the reconfigurable conductivity of these domain walls is
experimentally demonstrated, showcasing their potential for ultra-scaled device
applications. Our findings represent a pivotal advancement in understanding the
structural and electronic properties of wurtzite ferroelectric domain walls and
lay the groundwork for fundamental physics studies and device applications.
