Observation of Yu-Shiba-Rusinov states in superconducting graphene
arXiv:2010.10377
Abstract
When magnetic atoms are inserted inside a superconductor, the superconducting order is locally depleted as a result of the antagonistic nature of magnetism and superconductivity1. Thereby, distinctive spectral features, known as Yu-Shiba-Rusinov states, appear inside the superconducting gap2-4. The search for Yu-Shiba-Rusinov states in different materials is intense, as they can be used as building blocks to promote Majorana modes5 suitable for topological quantum computing6. Here we report the first realization of Yu-Shiba-Rusinov states in graphene, a non-superconducting 2D material, and without the participation of magnetic atoms. We induce superconductivity in graphene by proximity effect7-9 brought by adsorbing nanometer scale superconducting Pb islands. Using scanning tunneling microscopy and spectroscopy we measure the superconducting proximity gap in graphene and we visualize Yu-Shiba-Rusinov states in graphene grain boundaries. Our results reveal the very special nature of those Yu-Shiba-Rusinov states, which extends more than 20 nm away from the grain boundaries. These observations provide the long sought experimental confirmation that graphene grain boundaries host local magnetic moments10-14 and constitute the first observation of Yu-Shiba-Rusinov states in a chemically pure system.
References in corpus (21)
- Magic-angle graphene superlattices: a new platform for unconventional superconductivity
- Observation of Majorana Fermions in Ferromagnetic Atomic Chains on a Superconductor
- Bipolar supercurrent in graphene
- Majorana Zero Modes and Topological Quantum Computation
- Atomic-scale control of graphene magnetism using hydrogen atoms
- The Zak phase and the existence of edge states in graphene
- First direct observation of a nearly ideal graphene band structure
- Unravelling the intrinsic and robust nature of van Hove singularities in twisted bilayer graphene
- Long range coherent magnetic bound states in superconductors
- Quasiparticle Chirality in Epitaxial Graphene Probed at the Nanometer Scale
- Tuning the coupling of an individual magnetic impurity to a superconductor: quantum phase transition and transport
- Role of pseudospin in quasiparticle interferences in epitaxial graphene probed by high-resolution scanning tunneling microscopy
- On the use of STM superconducting tips at very low temperatures
- Proximity coupling in superconductor-graphene heterostructures
- Dangling bonds and magnetism of grain boundaries in graphene
- Proximity-induced Shiba states in a molecular junction
- Parallel Transport of Electrons in Graphene Parallels Gravity
- Scanning Tunneling Spectroscopy of Proximity Superconductivity in Epitaxial Multilayer Graphene
- An upper bound for the magnetic force gradient in graphite
- Probing local moments in nanographenes with electron tunneling spectroscopy
- Majorana zero modes