5d铱氧化物中自旋轨道耦合与电子关联作用具有相同的能量量级，它们的竞争和共存有望形成多种新奇的量子态，包括新型高温超导、Weyl半金属、拓扑莫特绝缘体等。与铜基和铁基超导体中3d轨道电子相比，铱氧化物中5d电子的有效角动量为1/2的电子态有很多不同与新颖之处，在5d电子系统中实现高温超导态有望为高温超导机理的研究带来重要的突破。目前，理论与实验已发现Sr2IrO4展现出很多与铜基超导体相似的特性，包括绝缘反铁磁基态、费米弧、V型能隙等。然而，限于载流子有效掺杂浓度及均匀度等方面的困难，还未能观测到零电阻及迈斯纳效应等超导的直接证据。本项目拟通过分子束外延方法制备单个及多个晶胞厚度的SrIrO3超薄膜，通过表面及界面掺杂以获得更均匀分布的有效载流子掺杂，并应用原位角分辨光电子谱及原位输运测试研究维度及电子掺杂对其电子结构与输运性质的调控，以探索可能的高温超导态及其超导配对机制。

Spin orbit coupling and electron correlation in 5d iridates are of similar energy scale and their interplay has been predicted to yield various exotic new quantum phenomena, such as high Tc superconductivity, Weyl semimetal and topological Mott insulator. The effective spin ½ electrons of 5d electrons in iridates has some similarities and differences compared to 3d electrons in cuprates, providing a new test bed for numerous models of high Tc superconductivity. Up to date, Sr2IrO4 has been experimentally demonstrated to share many promising similarities with cuprates, including antiferromagnetic ground state, Fermi arc and V shape energy gap. Nevertheless, no direct evidences such as zero resistivity and Meissner effect have been ever observed yet which possibly due to the inhomogeneous and low effective charge carrier doping. Here, we propose to achieve more homogeneous and higher density of charge carrier doping through surface and interface doping of ultra-thin SrIrO3 epitaxial films by oxide molecular epitaxy (MBE). Through in situ angle resolved photoemission spectroscopy (ARPES) and in situ transport measurements, we will investigate the electronic structure and the possible superconductivity in ultra thin SrIrO3 epitaxial films.