Abstract
We have investigated structural, transport, and optical properties of tensile strained (Sr1-xLax)3Ir2O7 (x=0, 0.025, 0.05) epitaxial thin films. While high-Tc superconductivity is predicted theoretically in the system, we have observed that all of the samples remain insulating with finite optical gap energies and Mott variable-range hopping characteristics in transport. Cross-sectional scanning transmission electron microscopy indicates that structural defects such as stacking faults appear in this system. The insulating behavior of the La-doped Sr3Ir2O7 thin films is presumably due to disorder-induced localization and ineffective electron doping of La, which brings to light the intriguing difference between epitaxial thin films and bulk single crystals of the iridates.
| Original language | English |
|---|---|
| Article number | 024803 |
| Journal | Physical Review Materials |
| Volume | 2 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 14 2018 |
Bibliographical note
Publisher Copyright:© 2018 American Physical Society.
Funding
We acknowledge the support of NSF Grants No. DMR-1454200 (for thin-film synthesis and characterizations), No. DMR-1265162 and No. DMR-1712101 (for target synthesis), and No. DMR-1262261 (for infrared spectroscopy).
| Funders | Funder number |
|---|---|
| U.S. Department of Energy Chinese Academy of Sciences Guangzhou Municipal Science and Technology Project Oak Ridge National Laboratory Extreme Science and Engineering Discovery Environment National Science Foundation National Energy Research Scientific Computing Center National Natural Science Foundation of China | 1454200, DMR-1265162, DMR-1262261, DMR-1712101 |
ASJC Scopus subject areas
- General Materials Science
- Physics and Astronomy (miscellaneous)