标题： 工程化超导接触透明于双极石墨烯 显示英文标题

标题： Engineering superconducting contacts transparent to a bipolar graphene

摘要： 石墨烯卓越的电子迁移率、栅极可调性以及与超导材料的接触透明性使其成为探索超导邻近效应的理想材料。 然而，石墨烯与超导体之间的功函数差异会导致接触区域不可避免地掺杂石墨烯，在空穴掺杂区域形成p-n结并降低接触透明性。 这给利用石墨烯双极性的器件实现带来了挑战。 为解决这一限制，我们开发了一种二维超导接触的新制造方案，该方案允许对与超导体接触的石墨烯和石墨烯沟道中的电荷浓度和极性进行独立控制。 通过测量接触透明性、电导增强和约瑟夫森耦合，证实了对石墨烯两种极性的透明接触。 此外，我们在负填充因子{\nu } = -2 的量子霍尔边缘态中展示了安德列夫过程。 该方案将为实现各种利用石墨烯双极性与超导性相结合的理论设想开辟新途径。 显示英文摘要

摘要： Graphene's exceptional electronic mobility, gate-tunability, and contact transparency with superconducting materials make it ideal for exploring the superconducting proximity effect. However, the work function difference between graphene and superconductors causes unavoidable doping of graphene near contacts, forming a p-n junction in the hole-doped regime and reducing contact transparency. This challenges the device implementation that exploits graphene's bipolarity. To address this limitation, we developed a new fabrication scheme for two-dimensional superconducting contacts that allows independent control over charge concentration and polarity for both the graphene in contact with superconductors and the graphene channel. Contact transparency, conductance enhancement, and Josephson coupling were measured to confirm transparent contacts to both polarities of graphene. Moreover, we demonstrated the Andreev process in the quantum Hall edge state at a negative filling factor of {\nu} = -2. This scheme will open avenues for realizing various theoretical propositions utilizing the bipolarity of graphene combined with superconductivity.