  Since the dramatic interface enhancement of superconducting transition
temperature (Tc) was reported in one unit-cell FeSe film grown on SrTiO3
substrate (1-UC FeSe/STO) by molecular beam epitaxy (MBE), related research on
this system has become a new frontier in condensed matter physics. In this
paper, we present a brief review on this rapidly developing field, mainly
focusing on the superconducting properties of 1-UC FeSe/STO. Experimental
evidences for the high-temperature superconductivity in 1-UC FeSe/STO,
including the direct evidences revealed by transport and diamagnetic
measurements, and other evidences from scanning tunneling microscope (STM) and
angle-resolved photoemission spectroscopy (ARPES), are overviewed. Potential
mechanisms of the enhanced superconductivity are discussed. There are
accumulating arguments suggesting that the strengthened Cooper pairing in 1-UC
FeSe/STO originates from the interface effects, specifically charge transfer
and coupling to phonon modes in TiO2 plane. The study of superconductivity in
1-UC FeSe/STO not only sheds a new light on the mechanism of high-temperature
superconductors with layered structures, but also provides the insight to
explore new superconductors by interface engineering.
