1. High-temperature superconductivity and its robustness against magnetic polarization in monolayer FeSe on EuTiO3
- Author
-
Ryan Day, Andrea Damascelli, Ke Zou, Hyungki Shin, Hsiang-Hsi Kung, Chong Liu, Andrin Doll, Giorgio Levy, Bruce A. Davidson, Cinthia Piamonteze, and Jan Dreiser
- Subjects
High-temperature superconductivity ,Materials science ,Photoemission spectroscopy ,02 engineering and technology ,01 natural sciences ,law.invention ,Condensed Matter::Materials Science ,Magnetization ,law ,Condensed Matter::Superconductivity ,0103 physical sciences ,Monolayer ,Antiferromagnetism ,Atomic physics. Constitution and properties of matter ,010306 general physics ,Materials of engineering and construction. Mechanics of materials ,Superconductivity ,Spin polarization ,Condensed matter physics ,Transition temperature ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,TA401-492 ,Condensed Matter::Strongly Correlated Electrons ,0210 nano-technology ,QC170-197 - Abstract
Spin degree of freedom generally plays an important role in unconventional superconductivity. In many of the iron-based compounds, superconductivity is found in close proximity to long-range antiferromagnetic order, whereas monolayer FeSe grown on SrTiO3, with enhanced superconductivity, exhibits no magnetic or nematic ordering. Here we grow monolayer and multilayer FeSe on antiferromagnetic EuTiO3(001) layers, in an effort to introduce a spin polarization in proximity to the superconductivity of FeSe. By X-ray magnetic dichroism, we observe an antiferromagnet–ferromagnet switching on Eu and Ti sites in EuTiO3 driven by the applied magnetic field, with no concomitant spin polarization on the Fe site of FeSe. Transport measurements show enhanced superconductivity of monolayer FeSe on EuTiO3 with a transition temperature of ~30 K. The band structure revealed by photoemission spectroscopy is analogous to that of FeSe/SrTiO3. Our work creates a platform for the interplay of spin and unconventional superconductivity in the two-dimensional limit.
- Published
- 2021