Proximity of a topological insulator (TI) surface with a magnetic insulator (MI) can open an exchange gap at the Dirac point leading to exploration of surface quantum anomalous Hall effect. An important requirement to observe the above effect is to prevent the topological breakdown of the surface states (SSs) due to various interface coupling effects and to tune the Fermi level at the interface near the Dirac point. In this work, we demonstrate the growth of high-quality c-axis oriented strain-free layered films of TI, Bi₂Se₃, on amorphous SiO₂ substrate in proximity to an MI, europium sulfide (EuS), that show stronger weak anti-localization response from the surface than previous studies with epitaxially interfaced heterostructures. Importantly, we find gate and magnetic field cooling modulated localization effects in the SSs, attributed to the position of interface Fermi level within the band gap that is also corroborated from our positron annihilation spectroscopy measurements. Furthermore, our experiments provide a direct evidence of gate-controlled enhanced interface magnetism in EuS arising from the carrier mediated Ruderman–Kittel–Kasuya–Yosida interactions across the Bi₂Se₃/EuS interface. These findings demonstrate the existence of complex interfacial phenomena affecting the localization response of the SSs that might be important in proximity engineering of the TI surface to observe surface quantum Hall effects.

拓扑绝缘体（TI）表面与磁性绝缘体（MI）的接近度可以在Dirac点处打开交换间隙，从而导致对表面量子异常霍尔效应的探索。观察上述效果的一项重要要求是防止由于各种界面耦合效应而引起的表面态（SSs）拓扑破坏，并在Dirac点附近的界面处调整费米能级。在这项工作中，我们证明了在无定形SiO ₂上生长高质量的TI，Bi ₂ Se _3的c轴取向无应变层状膜。与以前的外延界面异质结构研究相比，接近MI的硫化euro（EuS）衬底具有更强的弱抗定位响应能力。重要的是，我们发现SS中的栅极和磁场冷却调制的局部化效应，归因于带隙内界面费米能级的位置，这也从我们的正电子an没光谱测量中得到了证实。此外，我们的实验提供了由Bi ₂ Se _3上的载体介导的Ruderman-Kittel-Kasuya-Yosida相互作用引起的EuS中门控增强界面磁性的直接证据。/ EuS界面。这些发现表明存在影响SS定位反应的复杂界面现象，这在TI表面的邻近工程中观察表面量子霍尔效应可能很重要。