TY - JOUR
T1 - Tunable inversion symmetry to control indirect-to-direct band gaps transitions
AU - Lu, Xue Zeng
AU - Rondinelli, James M.
N1 - Funding Information:
We thank Prof. Hongjun Xiang for support of the genetic algorithm structure search code. X.-Z.L. thanks Dr. Hongwei Wang for the helpful discussion in the Wannier90 calculations. X.-Z.L. and J.M.R. were supported by the National Science Foundation (NSF) through the Pennsylvania State University MRSEC under Award No. DMR-1420620. DFT calculations were performed on the CARBON cluster at the Center for Nanoscale Materials [Argonne National Laboratory, supported by DOE-BES (Grant No. DE-AC02-06CH11357)], the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by NSF (Grant No. ACI-1548562), and the DoD Supercomputing Resource Centers supported by the High Performance Computing and Modernization Program of the DoD.
PY - 2018/5/17
Y1 - 2018/5/17
N2 - Electric-field tunable indirect-to-direct band gap transitions occur in thin-film silicon and transition metal dichalcogenides; however, they remain challenging to access in three-dimensional transition metal oxides. Very recently, an unusual polar-to-nonpolar phase transition under epitaxial strain was discovered in A3B2O7 hybrid improper ferroelectrics (HIFs), which supports controllable dielectric anisotropy and magnetization. Here we examine HIF (ABO3)1/(A′BO3)1 superlattices and AA′BB′O6 double perovskites and predict a competing nonpolar antiferroelectric phase, demonstrating it is hidden in hybrid improper ferroelectrics exhibiting corner-connected BO6 octahedra. Furthermore, we show the transition between the polar and nonpolar phases enables an in-plane electric field to control the indirect-to-direct band gap transition at the phase boundary in the (ABO3)1/(A′BO3)1 superlattices and AA′BB′O6 double perovskites, which may be tuned through static strain or chemical substitution. Our findings establish HIFs as a functional electronics class from which to realize direct gap materials and enables the integration of a broader palette of chemistries and compounds for linear and nonlinear optical applications.
AB - Electric-field tunable indirect-to-direct band gap transitions occur in thin-film silicon and transition metal dichalcogenides; however, they remain challenging to access in three-dimensional transition metal oxides. Very recently, an unusual polar-to-nonpolar phase transition under epitaxial strain was discovered in A3B2O7 hybrid improper ferroelectrics (HIFs), which supports controllable dielectric anisotropy and magnetization. Here we examine HIF (ABO3)1/(A′BO3)1 superlattices and AA′BB′O6 double perovskites and predict a competing nonpolar antiferroelectric phase, demonstrating it is hidden in hybrid improper ferroelectrics exhibiting corner-connected BO6 octahedra. Furthermore, we show the transition between the polar and nonpolar phases enables an in-plane electric field to control the indirect-to-direct band gap transition at the phase boundary in the (ABO3)1/(A′BO3)1 superlattices and AA′BB′O6 double perovskites, which may be tuned through static strain or chemical substitution. Our findings establish HIFs as a functional electronics class from which to realize direct gap materials and enables the integration of a broader palette of chemistries and compounds for linear and nonlinear optical applications.
UR - http://www.scopus.com/inward/record.url?scp=85059620988&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85059620988&partnerID=8YFLogxK
U2 - 10.1103/PhysRevMaterials.2.054409
DO - 10.1103/PhysRevMaterials.2.054409
M3 - Article
AN - SCOPUS:85059620988
VL - 2
JO - Physical Review Materials
JF - Physical Review Materials
SN - 2475-9953
IS - 5
M1 - 054409
ER -