Description | ABSTRACT: Molecular beam epitaxy (MBE) is an epitaxial process by which single-crystal thin films, heterostructures, and superlattices can be grown with near-atomic precision and the highest achievable purity. Therefore, MBE is known as one of the most advanced and controllable material synthesis methods, which has repeatedly made breakthroughs in the discovery of novel materials for fundamental science and modern electronic devices. In this talk, I will introduce the MBE growth of quantum materials, spanning from topological insulators to interfacial superconductors, and the pursuit of the new phenomena therein for quantum information science. I will focus on two solid-state platforms for topological quantum computation: the quantum anomalous Hall (QAH) insulator and interfacial superconductivity. The QAH insulator is a material in which the interior is insulating but electrons can travel with zero resistance along one-dimensional conducting edge channels. I will first briefly introduce the history towards the first experimental realization of the QAH effect [1,2] and then focus on the new quantum phenomenon in MBE-grown magnetic topological insulator multilayers, including the axion insulator [3], the QAH insulator with multiple edge channels [4], and the quest of Majorana physics in millimeter-size QAH/superconductor heterostructures [5]. I will then present the creation of interfacial superconductivity in an MBE-grown heterostructure formed by two non-superconducting materials. I will show that this new heterostructure fulfills the two essential ingredients for topological superconductivity and thus provide an alternative platform for the exploration of Majorana physics towards scalable topological quantum computations. References [1] Chang et al, Science 340, 167(2013). [2] Chang et al, Nature Mater. 14, 473(2015) [3] Xiao et al, Phys. Rev. Lett. 120, 056801 (2018) [4] Zhao et al, Nature 588, 419 (2020). [5] Kayyalha et al, Science 367, 64(2020) |
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