论文标题
硅表面手性超导性的证据
Evidence for chiral superconductivity on a silicon surface
论文作者
论文摘要
SI（111）底物上的SN ATATOM具有1/3单层覆盖范围，形成了一个二维三角adatom晶格，每个位置一个未配对的电子和一个反铁磁莫特绝缘状态。 SN层可以通过浓重的$ P $ -Type Si（111）底物调节孔掺杂并进行金属化，并在低温下变得超导。虽然当前未知超导状态的配对对称性，但三角形Adatom晶格固有的排斥相互作用和挫败感的组合为手性顺序参数的可能性打开了可能性。在这里，我们使用扫描隧道显微镜/光谱和准粒子干扰成像研究了SN/SI（111）的超导状态（111）。我们发现证据表明掺杂$ T_C $具有完全差的顺序参数，时间反转对称性破坏以及在超导域边缘附近的零偏置电导的强大增强。尽管每个证据都可能具有更平凡的解释，但我们的综合结果表明SN/SI（111）是一种非常规性的D-Wave超导体的诱人可能性。
Sn adatoms on a Si(111) substrate with 1/3 monolayer coverage form a two-dimensional triangular adatom lattice with one unpaired electron per site and an antiferromagnetic Mott insulating state. The Sn layers can be modulation hole-doped and metallized using heavily-doped $p$-type Si(111) substrates, and become superconducting at low temperatures. While the pairing symmetry of the superconducting state is currently unknown, the combination of repulsive interactions and frustration inherent to the triangular adatom lattice opens up the possibility for a chiral order parameter. Here, we study the superconducting state of Sn/Si(111) using scanning tunneling microscopy/spectroscopy and quasi-particle interference imaging. We find evidence for a doping-dependent $T_c$ with a fully gapped order parameter, the presence of time-reversal symmetry breaking, and a strong enhancement of the zero-bias conductance near the edges of the superconducting domains. While each individual piece of evidence could have a more mundane interpretation, our combined results suggest the tantalizing possibility that Sn/Si(111) is an unconventional chiral d-wave superconductor.
