The wurtzite structure is one of the most frequently found crystal structures in modern
semiconductors and its inherent spontaneous polarization is a defining materials property.
Despite this significance, confusion has been rampant in the literature with respect to the
orientation of the spontaneous polarization inside the unit cell of the wurtzite structure,
especially for the technologically very relevant III-N compounds (AlN, GaN, and InN). In
particular, the spontaneous polarization has been reported to either point up or down for the …