Wang, Y., Xie, Z., Guan, Y., Cao, J., Zhang, Y., Hu, G., Bai, Y., Wong, Y. H., Zeng, G., Huang, Z., Tan, C. K. (2026). Atomic-level revelation of spontaneous polarization orientation and piezoelectricity in ε -Ga2O3. Applied Physics Letters. https://doi.org/10.1063/5.0321241