Highly tunable junctions and non-local Josephson effect in magic-angle graphene tunnelling devices.
Journal
Nature nanotechnology
ISSN: 1748-3395
Titre abrégé: Nat Nanotechnol
Pays: England
ID NLM: 101283273
Informations de publication
Date de publication:
Jul 2021
Jul 2021
Historique:
received:
09
11
2020
accepted:
10
03
2021
pubmed:
5
5
2021
medline:
5
5
2021
entrez:
4
5
2021
Statut:
ppublish
Résumé
Magic-angle twisted bilayer graphene (MATBG) has recently emerged as a highly tunable two-dimensional material platform exhibiting a wide range of phases, such as metal, insulator and superconductor states. Local electrostatic control over these phases may enable the creation of versatile quantum devices that were previously not achievable in other single-material platforms. Here we engineer Josephson junctions and tunnelling transistors in MATBG, solely defined by electrostatic gates. Our multi-gated device geometry offers independent control of the weak link, barriers and tunnelling electrodes. These purely two-dimensional MATBG Josephson junctions exhibit non-local electrodynamics in a magnetic field, in agreement with the Pearl theory for ultrathin superconductors. Utilizing the intrinsic bandgaps of MATBG, we also demonstrate monolithic edge tunnelling spectroscopy within the same MATBG devices and measure the energy spectrum of MATBG in the superconducting phase. Furthermore, by inducing a double-barrier geometry, the devices can be operated as a single-electron transistor, exhibiting Coulomb blockade. With versatile functionality encompassed within a single material, these MATBG tunnelling devices may find applications in graphene-based tunable superconducting qubits, on-chip superconducting circuits and electromagnetic sensing.
Identifiants
pubmed: 33941915
doi: 10.1038/s41565-021-00894-4
pii: 10.1038/s41565-021-00894-4
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
769-775Subventions
Organisme : NSF | Directorate for Mathematical & Physical Sciences | Division of Physics (PHY)
ID : DMR-1809802
Organisme : NSF | Directorate for Mathematical & Physical Sciences | Division of Physics (PHY)
ID : DMR-1231319
Organisme : United States Department of Defense | United States Army | U.S. Army Research, Development and Engineering Command | Army Research Office (ARO)
ID : W911NF-17-S-0001
Organisme : DOE | SC | Basic Energy Sciences (BES)
ID : DE-SC0001819
Organisme : DOE | SC | Basic Energy Sciences (BES)
ID : DE-SC0019300
Organisme : MEXT | Japan Society for the Promotion of Science (JSPS)
ID : JPMXP0112101001
Organisme : MEXT | Japan Society for the Promotion of Science (JSPS)
ID : JP20H00354
Organisme : MEXT | JST | Core Research for Evolutional Science and Technology (CREST)
ID : CREST(JPMJCR15F3)
Organisme : MEXT | JST | Core Research for Evolutional Science and Technology (CREST)
ID : CREST(JPMJCR15F3), JST
Organisme : Gordon and Betty Moore Foundation (Gordon E. and Betty I. Moore Foundation)
ID : GBMF9643
Informations de copyright
© 2021. The Author(s), under exclusive licence to Springer Nature Limited.
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