Related Experiment Video
Updated: Jan 3, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Light-Induced Currents at Domain Walls in Multiferroic BiFeO3
Burak Guzelturk1,2, Antonio B Mei3, Lei Zhang4
1Department of Materials Science and Engineering , Stanford University , Stanford , California 94305 , United States.
Nano Letters
|November 21, 2019
Summary
Domain walls in multiferroic Bismuth Ferrite (BiFeO3) films efficiently separate photogenerated charges, leading to significant photocurrents. This study reveals domain walls as key to understanding Bismuth Ferrite
Area of Science:
- Condensed Matter Physics
- Materials Science
- Optoelectronics
Background:
- Multiferroic Bismuth Ferrite (BiFeO3) films exhibit stripe domains and generate voltages under illumination.
- The mechanism behind this optoelectronic response in BiFeO3 remains unclear.
Purpose of the Study:
- To investigate the charge separation mechanisms responsible for the optoelectronic response in BiFeO3 films.
- To quantitatively measure light-induced currents and their directions without physical contact.
Main Methods:
- Contact-free measurement of light-induced currents using terahertz (THz) radiation detection.
- Analysis of epitaxial BiFeO3 films with both periodic stripe domains and monodomain structures.
Main Results:
- Photocurrent in stripe domain BiFeO3 is dominated by charge separation across domain walls.
- Monodomain BiFeO3 shows photovoltaic response from bulk shift current due to non-centrosymmetry.
- Domain wall charge separation yields photocurrents 2 orders of magnitude higher than bulk effects.
Conclusions:
- Domain walls in BiFeO3 act as efficient nanoscale junctions for photogenerated charge separation.
- Domain-wall-engineered BiFeO3 films show promise for ferroelectric optoelectronics.
- These films are potential candidates for bias-free, strong terahertz emitters.
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