Temporal and spatial tracking of ultrafast light-induced strain and polarization modulation in a ferroelectric thin film.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 37967179.
- Also identified by DOI 10.1126/sciadv.adi1160 and PMC identifier 10651133.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Ultrashort light pulses induce rapid deformations of crystalline lattices. In ferroelectrics, lattice deformations couple directly to the polarization, which opens the perspective to modulate the electric polarization on an ultrafast time scale. Here, we report on the temporal and spatial tracking of strain and polar modulation in a single-domain BiFeO<sub>3</sub> thin film by ultrashort light pulses. To map the light-induced deformation of the BiFeO<sub>3</sub> unit cell, we perform time-resolved optical reflectivity and time-resolved x-ray diffraction. We show that an optical femtosecond laser pulse generates not only longitudinal but also shear strains. The longitudinal strain peaks at a large amplitude of 0.6%. The access of both the longitudinal and shear strains enables to quantitatively reconstruct the ultrafast deformation of the unit cell and to infer the corresponding reorientation of the ferroelectric polarization direction in space and time. Our findings open new perspectives for ultrafast manipulation of strain-coupled ferroic orders.