2025/03/17 by Liu, Zhijie, Ma, Xingyue, Chen, Lan +6
#Computational Physics (physics.comp-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2503.13027
Electrostatic dielectric capacitors are foundational to advance the electronics and electric power devices due to their ultrafast charging/discharging capability and high-power density. However, the low energy density limits the potential for next generation devices in terms of miniaturization and integration. We propose a strategy that relies on inducing a field-driven phase transition that we denote paraelectric-metaparaelectric, which yields an ultrahigh energy density in III-nitrides. III-nitride compounds (Al, Sc, B)N with certain cation concentrations possess a nonpolar hexagonal ground phase which could transform into a polar wurtzite phase under a very large electric field, which is denoted as metaparaelectric with nearly null hysteresis P-E loop. This paraelectric-metaparaelectric transition leads to a polarization saturation at large electric field. The corresponding P-E loop displays a giant energy density of 308 J/cm3 with high efficiency nearly 100%. The proposed paraelectric-metaparaelectric phase transition strategy in nitrides opens an avenue to design of next generation high performance dielectrics.