Liu Chaofei, Chen Cheng, Liu Xiaoqiang, Wang Ziqiao, Liu Yi, Ye Shusen, Wang Ziqiang, Hu Jiangping, Wang Jian
International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
Department of Physics, Boston College, Chestnut Hill, MA 02467, USA.
Sci Adv. 2020 Mar 25;6(13):eaax7547. doi: 10.1126/sciadv.aax7547. eCollection 2020 Mar.
Majorana zero modes (MZMs) that obey the non-Abelian statistics have been intensively investigated for potential applications in topological quantum computing. The prevailing signals in tunneling experiments "fingerprinting" the existence of MZMs are the zero-energy bound states (ZEBSs). However, nearly all of the previously reported ZEBSs showing signatures of the MZMs are observed in difficult-to-fabricate heterostructures at very low temperatures and additionally require applied magnetic field. Here, by using in situ scanning tunneling spectroscopy, we detect the ZEBSs upon the interstitial Fe adatoms deposited on two different high-temperature superconducting one-unit-cell iron chalcogenides on SrTiO(001). The spectroscopic results resemble the phenomenological characteristics of the MZMs inside the vortex cores of topological superconductors. Our experimental findings may extend the MZM explorations in connate topological superconductors toward an applicable temperature regime and down to the two-dimensional (2D) limit.
服从非阿贝尔统计的马约拉纳零模（MZMs）因其在拓扑量子计算中的潜在应用而受到深入研究。在隧道实验中“指纹识别”MZMs存在的主要信号是零能束缚态（ZEBSs）。然而，几乎所有先前报道的显示MZMs特征的ZEBSs都是在极低温下难以制造的异质结构中观察到的，并且还需要施加磁场。在这里，通过使用原位扫描隧道光谱，我们在沉积在SrTiO(001)上的两种不同的高温超导单胞铁硫族化合物上的间隙铁吸附原子上检测到了ZEBSs。光谱结果类似于拓扑超导体涡旋核内MZMs的唯象特征。我们的实验发现可能会将原生拓扑超导体中的MZM探索扩展到适用的温度范围，并降至二维（2D）极限。
