Angle-resolved photoemission spectroscopy studies on 1uc FeSe/oxide interface superconductors
Abstract
<p indent="0mm">The existence of high-temperature superconductivity in 1uc FeSe/oxide is one of the key discoveries in the field of condensed matter physics in recent years. 1uc FeSe/oxide is the thinnest high-temperature superconductor realized so far, and it has a superconducting pairing strength considerably higher than that of bulk FeSe. More interestingly, the substantial enhancement of the superconducting pairing temperature only occurs when FeSe is single-unit-cell thick, while the second unit-cell of FeSe/SrTiO<sub>3</sub> does not exhibit superconductivity. <italic>In-situ</italic> interface engineering and angle-resolved photoemission spectroscopy (ARPES) studies have played a crucial role in resolving the interfacial superconducting mechanism and enhancing the superconducting pairing strength according to the underlying physical mechanism. This paper mainly reviews the research progress of the combined interfacial engineering and <italic>in-situ</italic> ARPES studies of 1uc FeSe/oxide interfacial superconductivity and explains the characteristics of electronic structure and superconducting gap, interface engineering that help show the superconductivity enhancement mechanism, superconductivity enhancement by tuning the interfacial oxides. The results of these experiments point out workable routes for designing new interfaces with high-temperature superconductivity.</p>
