Chiral quasiparticle tunneling between quantum Hall edges in proximity with a superconductor
ORAL
Abstract
We study a two-terminal graphene Josephson junction with contacts shaped to form a narrow constriction,
less than 100 nm in length. The contacts are made from type-II superconducting contacts and able to withstand
magnetic fields high enough to reach the quantum Hall regime in graphene. In this regime, the device
conductance is determined by edge states, plus the contribution from the constricted region. In particular,
the constriction area can support supercurrents up to fields of ∼2.5 T. Additionally, enhanced conductance
is observed through a wide range of magnetic fields and gate voltages. This additional conductance and the
appearance of supercurrent is attributed to the tunneling between counterpropagating quantum Hall edge states
along opposite superconducting contacts.
Published in: M.T. Wei, et.al. PHYSICAL REVIEW B 100, 121403(R) (2019)
less than 100 nm in length. The contacts are made from type-II superconducting contacts and able to withstand
magnetic fields high enough to reach the quantum Hall regime in graphene. In this regime, the device
conductance is determined by edge states, plus the contribution from the constricted region. In particular,
the constriction area can support supercurrents up to fields of ∼2.5 T. Additionally, enhanced conductance
is observed through a wide range of magnetic fields and gate voltages. This additional conductance and the
appearance of supercurrent is attributed to the tunneling between counterpropagating quantum Hall edge states
along opposite superconducting contacts.
Published in: M.T. Wei, et.al. PHYSICAL REVIEW B 100, 121403(R) (2019)
*CityU New Research Initiatives/Infrastructure Support from Central (APRC) No. 9610395, Hong Kong Research Grants Council (ECS) Project No. 9048125, ARO Award No. W911NF16-1-0122, NSF Awards No. ECCS-1610213 and No. DMR-1743907, Department of Energy, under Award No. DE-SC0002765, KAKENHI (Grants No. 38000131 and No. 17H01138).
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Presenters
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Ivan Borzenets
- Physics, City University of Hong Kong
- Department of Physics, City University of Hong Kong
- City Univ of Hong Kong