Reverse Chemical Switching of a Ferroelectric Film

Feb 25, 2009

(PhysOrg.com) -- Ferroelectric materials display a spontaneous electric polarization below the Curie temperature that can be reoriented, typically by applying an electric field. In this study, researchers from Argonne, Northern Illinois University, and The University of Pennsylvania have demonstrated that the chemical environment can control the polarization orientation in an ultrathin ferroelectric film.

This is complementary to recent predictions that polarization can affect surface chemistry and illuminates potential applications in sublithographic patterning and electrically tunable catalysts.

In situ synchrotron X-ray scattering measurements showed that high or low oxygen partial pressure induces outward or inward polarization, respectively, in an ultrathin PbTiO3 film. While X-ray scattering is not sensitive to interfacial charge from polarization, it is very sensitive to the atomic positions in the crystal structure of a ferroelectric film that determine its polarization.

The image shows hysteresis in the ferroelectric film structure as a function of oxygen partial pressure indicating polarization switching. The most intense (red) feature is the PbTiO3 Bragg peak. By following the behavior in situ, one sees that chemical potential affects ferroelectric film polarization in the same way as electric potential. In combination with ab initio based modeling, these experiments show that the chemical environment can play a dominant role in the behavior of nanoscale ferroelectrics.

More information:
• Wang et al., "Reversible Chemical Switching of a Ferroelectric Film," Phys. Rev. Lett., 102, 047601 (2009),
• J. Hinka, "A Viewpoint on Reversible Chemical Switching of a Ferroelectric Film," Physics. 2, 8 (2009) (online)

Provided by Argonne National Laboratory

Explore further: World's most complex crystal simulated

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Controlling core switching in Pac-man disks

Dec 24, 2014

Magnetic vortices in thin films can encode information in the perpendicular magnetization pointing up or down relative to the vortex core. These binary states could be useful for non-volatile data storage ...

World's most complex crystal simulated

Dec 24, 2014

The most complicated crystal structure ever produced in a computer simulation has been achieved by researchers at the University of Michigan. They say the findings help demonstrate how complexity can emerge ...

Atoms queue up for quantum computer networks

Dec 24, 2014

In order to develop future quantum computer networks, it is necessary to hold a known number of atoms and read them without them disappearing. To do this, researchers from the Niels Bohr Institute have developed ...

New video supports radiation dosimetry audits

Dec 23, 2014

The National Physical Laboratory (NPL), working with the National Radiotherapy Trials Quality Assurance Group, has produced a video guide to support physicists participating in radiation dosimetry audits.

Ultrasounds dance the 'moonwalk' in new metamaterial

Dec 23, 2014

Metamaterials have extraordinary properties when it comes to diverting and controlling waves, especially sound and light: for instance, they can make an object invisible, or increase the resolving power of ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.