Speaker
Description
A recent study on FeSe thin films grown on different substrates revealed that films on CaF$_2$ substrate has the maximum $\textit{T$_c$}$ ~15 K. However, the monolayer FeSe grown on SrTiO$_3$ (STO) substrate generated much research interest when superconductivity was observed at $\textit{T$_c$}$ above 100 K by means of $\textit{in situ}$ four-point probe electrical transport measurements. There are different factors that were identified, such as the tensile strain and electron doping, which contributed to the enhancement of the $\textit{T$_c$}$. To investigate the interface effect in the superconductivity of monolayer FeSe, we calculated the structural and electronic properties of monolayer FeSe grown on CaF$_2$. Only electron pockets are observed around the M point for both NM and AFM configurations. The same feature is observed in experimental studies on 1ML FeSe/STO. This suggests that the mechanism of superconductivity of single-layer FeSe on STO and CaF$_2$ might be the same. However, further experimental research on 1ML FeSe/CaF$_2$ is necessary to verify our results.
