Work

Anisotropic light-electron-phonon coupling and ultrafast carrier separation in ferroelectric BaTiO3

Year: 2026

Type: article

Abstract: Ferroelectric materials with built-in electric fields are useful for ultrafast electronics and conversion of light into electrical energy, yet the interaction of carrier motion with ultrafast relaxation processes remains nontrivial. Combining ultrafast electron diffraction with electron microscopy of electromagnetic fields, we capture ultrafast lattice dynamics and nanometer-scale carrier transport in ferroelectric BaTiO 3 . We demonstrated that BaTiO 3 reacts to light with an anisotropic electron-phonon coupling that depends on the optical polarization of the excitation light. Excited electrons relax two times faster into phonons when the optical electric field aligns to the ferroelectric symmetry break. Furthermore, ultrafast electron electrometry captures the motion and separation of photo-excited electron-hole pairs in presence of the ferroelectric field. These combined results provide insight into the tangled and anisotropic interaction of photons with phonons and the ferroelectric field, producing phonons and voltages in a stepwise reaction path.

Source: Communications Physics

DOI: 10.1038/s42005-026-02922-y

Authors: A. B. Swain, S. Kale, R. Soni, P. Baum

Institutions: University of Konstanz, Indian Institute of Science Education and Research Berhampur

Language: English

Topic: Ferroelectric and Piezoelectric Materials

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,990

Funder: Deutsche Forschungsgemeinschaft