Research Themes +
Energy Technologies Area (ETA) researchers are continually building on the strong scientific foundation we have developed over the past 50 years. We address the world’s most pressing climate challenges by bringing to market energy-efficient innovations across the buildings, transportation, and industrial sectors. ETA is at the forefront of developing better batteries for electric vehicles; improving the country's aging electrical grid and innovating distributed energy and storage solutions; developing grid-interactive, efficient buildings; and providing the most comprehensive market and data analysis worldwide for renewable technologies like wind and solar.
Strategic Initiatives +
The Energy Technologies Area (ETA) Strategic Plan is the guiding force for our research and development for the next ten years. It clearly charts a path toward clean-energy solutions and focuses on five detailed Strategic Initiatives. The Plan provides an in-depth look at how ETA is accelerating research to provide affordable, clean energy to all while accomplishing deep, economy-wide decarbonization, looking to avoid a rise in global average temperature while simultaneously developing solutions to increase humanity's resilience to extreme weather volatility.
Publications
News +
For media inquiries,
please contact ETA
Interim Communications Manager
Kiran Julin

kjulin@lbl.gov
About Us +
The Energy Technologies Area (ETA) is unique in translating fundamental scientific discoveries into scalable technology adoption. Our approach combines an understanding of the marketplace and the role of state and federal regulation and policies. ETA's research drives real-world, practical results that affect and improve the everyday lives of Americans and those across the globe. Saving energy and battling the Climate Crisis are key to the foundation of our research, which is driven by technoeconomic analysis and in-lab experimentation and discovery.

Phase coexistence and electric-field control of toroidal order in oxide superlattices

Publication Type

Journal Article

Authors

Damodaran, A.R, J.D Clarkson, Z Hong, H B Liu, A.K Yadav, C.T Nelson, S.-L Hsu, M.R McCarter, K.-D Park, V Kravtsov, A Farhan, Y Dong, Z Cai, H Zhou, P Aguado-Puente, P García-Fernández, J Íñiguez, J Junquera, A Scholl, M.B Raschke, L.-Q Chen, D.D Fong, Ramamoorthy Ramesh, L.W Martin

DOI

10.1038/NMAT4951

Abstract

Systems that exhibit phase competition, order parameter coexistence, and emergent order parameter topologies constitute a major part of modern condensed-matter physics. Here, by applying a range of characterization techniques, and simulations, we observe that in PbTiO"3/SrTiO"3 superlattices all of these effects can be found. By exploring superlattice period-, temperature- and field-dependent evolution of these structures, we observe several new features. First, it is possible to engineer phase coexistence mediated by a first-order phase transition between an emergent, low-temperature vortex phase with electric toroidal order and a high-temperature ferroelectric a"1/a"2 phase. At room temperature, the coexisting vortex and ferroelectric phases form a mesoscale, fibre-textured hierarchical superstructure. The vortex phase possesses an axial polarization, set by the net polarization of the surrounding ferroelectric domains, such that it possesses a multi-order-parameter state and belongs to a class of gyrotropic electrotoroidal compounds. Finally, application of electric fields to this mixed-phase system permits interconversion between the vortex and the ferroelectric phases concomitant with order-of-magnitude changes in piezoelectric and nonlinear optical responses. Our findings suggest new cross-coupled functionalities. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.

Journal

Nature Materials

Volume

Year of Publication

2017

ISSN

14761122

Notes

cited By 50

Research Areas

Ramesh Lab