skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on October 25, 2018

Title: Engineering an Insulating Ferroelectric Superlattice with a Tunable Band Gap from Metallic Components

The recent discovery of “polar metals” with ferroelectriclike displacements offers the promise of designing ferroelectrics with tunable energy gaps by inducing controlled metal-insulator transitions. Here in this work, we employ first-principles calculations to design a metallic polar superlattice from nonpolar metal components and show that controlled intermixing can lead to a true insulating ferroelectric with a tunable band gap. We consider a 2/2 superlattice made of two centrosymmetric metallic oxides, La 0.75Sr 0.25MnO 3 and LaNiO 3, and show that ferroelectriclike displacements are induced. The ferroelectriclike distortion is found to be strongly dependent on the carrier concentration (Sr content). Further, we show that a metal-to-insulator (MI) transition is feasible in this system via disproportionation of the Ni sites. Such a disproportionation and, hence, a MI transition can be driven by intermixing of transition metal ions between Mn and Ni layers. Finally, as a result, the energy gap of the resulting ferroelectric can be tuned by varying the degree of intermixing in the experimental fabrication method.
Authors:
 [1] ; ORCiD logo [2] ;  [1]
  1. Vanderbilt Univ., Nashville, TN (United States). Department of Physics and Astronomy; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
Publication Date:
Grant/Contract Number:
AC05-00OR22725; FG02-09ER46554
Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 119; Journal Issue: 17; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
OSTI Identifier:
1422580
Alternate Identifier(s):
OSTI ID: 1404745