Flexoelectricity in amorphous hafnium oxide (HfO2)

• DOI: 10.1063/5.0220532
• Publication Date: 2024-10-21T16:49:51Z
• Authors: Daniel Moreno-Garcia; Kaitlin M. Howell; Luis Guillermo Vi...
• Keywords: Flexoelectricity; Hafnium

Flexoelectricity, inherent in all materials, offers a promising alternative to piezoelectricity for nanoscale actuation and sensing. However, its widespread application faces significant challenges: differentiating flexoelectric effects from those of other phenomena, verifying universality across material structures thicknesses, establishing comprehensive database coefficients different materials. This work introduces groundbreaking methodology that accurately isolates flexoelectricity piezoelectric, electrostrictive, electrostatic effects, with detection threshold extending below 1 fC/m. The robustness this method is demonstrated through amorphous hafnium oxide, successfully measuring coefficient 105 ± 10 pC/m. measurement signifies the first hafnia, as well any material. In addition, study compiles list published coefficients, revealing an important insight. relationship between material’s relative permittivity better approximated by quadratic proportionality. challenges traditional linear assumption proposed Kogan’s opens new avenues future research