Non-local transport measurements in hybrid quantum Hall - superconducting devices
arXiv:2310.02910 · doi:10.1103/PhysRevB.109.115416
Abstract
There has been a growing interest in hybrid quantum Hall (QH) superconductor devices, driven by the prospect to realize exotic ground states and excitations with non-abelian exchange statistics. While the existing experiments clearly demonstrate Andreev coupling between the edge states and the superconductors, the question remains whether the quantum coherence could propagate between several superconducting contacts via chiral channels. To answer this question, we have first extended the Landauer-Büttiker (LB) formalism to samples with one superconducting contact and found a remarkable agreement within a series of measurements related to each other via LB-type formulae. We have then switched to the case of multiple superconducting contacts, and found that we can describe the measurements self-consistently if we neglect the superconducting phase coherence between multiple contacts. We interpret this result as a negative answer to the question posed above: the phase correlations between multiple superconducting contacts are not established via micron-long quantum Hall edge states. Looking forward, our approach may find applications in the broader field of topological superconductivity and proximal structures. Possible violations of the self-consistency tests presented here may be used as an indication that superconducting phase coherence is induced in the quantum Hall edges.
References in corpus (21)
- Quantum Hall effect in graphene with superconducting electrodes
- Spin-triplet supercurrent carried by quantum Hall edge states through a Josephson junction
- Andreev reflection in the fractional quantum Hall state
- Andreev reflection at high magnetic fields: Evidence for electron and hole transport in edge states
- Andreev reflection and cyclotron motion at superconductor -- normal-metal interfaces
- Induced superconducting pairing in integer quantum Hall edge states
- Evidence for chiral supercurrent in quantum Hall Josephson junctions
- Conductance oscillations with magnetic field of a two-dimensional electron gas-superconductor junction
- Mechanisms of Andreev reflection in quantum Hall graphene
- Andreev reflection and strongly enhanced magnetoresistance oscillations in GaInAs/InP heterostructures with superconducting contacts
- Superconductivity and fermionic dissipation in quantum Hall edges
- Disorder in Andreev reflection of a quantum Hall edge
- Andreev transport in two-dimensional normal-superconducting systems in strong magnetic fields
- Supercurrent-enabled Andreev reflection in a chiral quantum Hall edge state
- Loss and decoherence at the quantum Hall - superconductor interface
- Vortex-enabled Andreev processes in quantum Hall-superconductor hybrids
- Geometrical effects on the downstream conductance in quantum-Hall--superconductor hybrid systems
- Magnetic focusing in normal-superconductor hybrid systems: a semiclassical analysis
- Majorana fermions on the quantum Hall edge
- Andreev reflection of quantum Hall states through a quantum point contact
- Quantum Hall Bogoliubov Interferometer