Proximitized 2D Materials

Igor Žutić, University at Buffalo

June 12, 2020

Advances in scaling down heterostructures and atomically thin two-dimensional (2D) materials suggest a novel approach to systematically design materials as well as to realize exotic states of matter. A given material can be transformed through proximity effects [1] whereby it acquires properties of its neighbors, for example, becoming superconducting, magnetic, topologically nontrivial, or with an enhanced spin-orbit coupling. Such proximity effects not only complement the conventional methods of designing materials but can also overcome their various limitations. In proximitized materials it is possible to realize properties that are not present in any constituent region of the considered heterostructure. After providing some background on proximity effects we discuss implications of magnetism leaking into initially a non-magnetic region [1-3]. Inspired by the 1937 prediction of Majorana fermions which are their own antiparticles, there is an intensive effort to realize their condensed-matter analogs [4]. Combined magnetic and superconducting proximity effects could enable elusive topologically protected Majorana bound states (MBS) for fault-tolerant quantum computing. We discuss our proposal for realizing such MBS in 2D platforms and the challenges for their experimental demonstration [5,6]. Recent measurements of proximity-induced topological superconductivity [7] provide novel opportunities for controlling MBS [8].

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