• 文献标题:   Strongly Coupled High-Quality Graphene/2D Superconducting Mo2C Vertical Heterostructures with Aligned Orientation
  • 文献类型:   Article
  • 作  者:   XU C, SONG SA, LIU ZB, CHEN L, WANG LB, FAN DX, KANG N, MA XL, CHENG HM, REN WC
  • 作者关键词:   graphene, 2d transition metal carbide, heterostructure, high quality, superconductivity
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Chinese Acad Sci
  • 被引频次:   28
  • DOI:   10.1021/acsnano.7b01638
  • 出版年:   2017

▎ 摘  要

Vertical heterostructures of two-dimensional (2D) crystals have led to the observations of numerous exciting physical phenomena and presented the possibilities for technological applications, which strongly depend on the quality, interface, relative alignment, and interaction of hybrids of graphene and superconductors offer a very the neighboring 2D crystals. The heterostructures or interesting platform to study mesoscopic superconductivity and the interplay of the quantum Hall effect with superconductivity. However, so far the heterostructures of graphene and 2D superconductors are fabricated by stacking, and consequently suffer from random relative alignment, weak interfacial interaction, and unavoidable interface contaminants. Here we report the direct growth of high-quality graphene/2D superconductor (nonlayered ultrathin alpha-Mo2C crystal) vertical heterostructures with uniformly well-aligned lattice orientation and strong interface coupling by chemical vapor deposition. In the heterostructure, both graphene and 2D alpha-Mo2C crystal show no defect, and the graphene is strongly compressed. Different from the previously reported graphene/superconductor heterostructures or hybrids, the strong interface coupling leads to a phase diagram of superconducting transition with multiple voltage steps being observed in the transition regime. Furthermore, we demonstrate the realization of highly transparent Josephson junction devices based on these strongly coupled high-quality heterostructures, in which a clear magnetic-field-induced Fraunhofer pattern of the critical supercurrent is observed.