Quasi-$Φ_0$-periodic supercurrent at quantum Hall transitions

• URL: http://arxiv.org/abs/2503.15384v1
• Date: Wed, 19 Mar 2025 16:22:56 GMT
• Title: Quasi-$Φ_0$-periodic supercurrent at quantum Hall transitions
• Authors: Ivan Villani, Matteo Carrega, Alessandro Crippa, Elia Strambini, Francesco Giazotto, Vaidotas Miseikis, Camilla Coletti, Fabio Beltram, Kenji Watanabe, Takashi Taniguchi, Stefan Heun, Sergio Pezzini,
• Abstract summary: Recent quantum interference studies suggest that QH edge states can effectively mediate a supercurrent across high-quality graphene weak links.<n>We employ a back-gated graphene Josephson junction, comprising high-mobility CVD-grown graphene encapsulated in hexagonal Boron Nitride (hBN) and contacted by Nb leads.<n>Superconducting pockets are detected persisting beyond the QH onset, up to 2.4 T, hence approaching the upper critical field of the Nb contacts.
• Score: 31.269816893043046
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The combination of superconductivity and quantum Hall (QH) effect is regarded as a key milestone in advancing topological quantum computation in solid-state systems. Recent quantum interference studies suggest that QH edge states can effectively mediate a supercurrent across high-quality graphene weak links. In this work we report the observation of a supercurrent associated with transitions between adjacent QH plateaus, where transport paths develop within the compressible two-dimensional bulk. We employ a back-gated graphene Josephson junction, comprising high-mobility CVD-grown graphene encapsulated in hexagonal Boron Nitride (hBN) and contacted by Nb leads. Superconducting pockets are detected persisting beyond the QH onset, up to 2.4 T, hence approaching the upper critical field of the Nb contacts. We observe an approximate $\Phi_0=h/2e$ periodicity of the QH-supercurrent as a function of the magnetic field, indicating superconducting interference in a proximitized percolative phase. These results provide a promising experimental platform to investigate the transport regime of percolative supercurrents, leveraging the flexibility of van der Waals devices.

Related papers

• Theory of fractional quantum Hall liquids coupled to quantum light and emergent graviton-polaritons [0.0]
  We study the dynamics of a $nu=1/3$ Laughlin state in a single-mode cavity with finite electric field gradients.<n>We find that the topological signatures of the FQH state remain robust against the non-local modulated cavity vacuum fluctuations.<n>By exploring the low-energy excited spectrum inside the FQH phase, we identify a new neutral quasiparticle, the graviton-polariton.
  arXiv  Detail & Related papers  (2024-05-20T18:00:36Z)
• Probing Site-Resolved Current in Strongly Interacting Superconducting Circuit Lattices [0.0]
  Transport measurements are fundamental for understanding condensed matter phenomena, from superconductivity to the fractional quantum Hall effect. Here we demonstrate the measurement of in-situ particle current in a superconducting circuit lattice and apply it to study transport in both coherent and bath-coupled lattices.
  arXiv  Detail & Related papers  (2024-03-18T17:08:04Z)
• Cooper quartets in interacting hybrid superconducting systems [44.99833362998488]
  Cooper quartets represent exotic fermion aggregates describing strongly correlated matter. We show how to design Cooper quartets in a double-dot system coupled to ordinary superconducting leads.
  arXiv  Detail & Related papers  (2024-01-08T19:28:15Z)
• Fragmented superconductivity in the Hubbard model as solitons in Ginzburg-Landau theory [39.58317527488534]
  Superconductivity and charge density waves are observed in close vicinity in strongly correlated materials. We investigate the nature of such an intertwined state of matter stabilized in the phase diagram of the elementary $t$-$tprime$-$U$ Hubbard model. We provide conclusive evidence that the macroscopic wave functions of the superconducting fragments are well-described by soliton solutions of a Ginzburg-Landau equation.
  arXiv  Detail & Related papers  (2023-07-21T18:00:07Z)
• Dipolar quantum solids emerging in a Hubbard quantum simulator [45.82143101967126]
  Long-range and anisotropic interactions promote rich spatial structure in quantum mechanical many-body systems. We show that novel strongly correlated quantum phases can be realized using long-range dipolar interaction in optical lattices. This work opens the door to quantum simulations of a wide range of lattice models with long-range and anisotropic interactions.
  arXiv  Detail & Related papers  (2023-06-01T16:49:20Z)
• Neural-network quantum states for ultra-cold Fermi gases [49.725105678823915]
  This work introduces a novel Pfaffian-Jastrow neural-network quantum state that includes backflow transformation based on message-passing architecture. We observe the emergence of strong pairing correlations through the opposite-spin pair distribution functions. Our findings suggest that neural-network quantum states provide a promising strategy for studying ultra-cold Fermi gases.
  arXiv  Detail & Related papers  (2023-05-15T17:46:09Z)
• Tuning long-range fermion-mediated interactions in cold-atom quantum simulators [68.8204255655161]
  Engineering long-range interactions in cold-atom quantum simulators can lead to exotic quantum many-body behavior. Here, we propose several tuning knobs, accessible in current experimental platforms, that allow to further control the range and shape of the mediated interactions.
  arXiv  Detail & Related papers  (2022-03-31T13:32:12Z)
• Effect of Emitters on Quantum State Transfer in Coupled Cavity Arrays [48.06402199083057]
  We study the effects of atoms in cavities which can absorb and emit photons as they propagate down the array. Our model is equivalent to previously examined spin chains in the one-excitation sector and in the absence of emitters.
  arXiv  Detail & Related papers  (2021-12-10T18:52:07Z)
• Quantum Phase Transitions in Long-Range Interacting Hyperuniform Spin Chains in a Transverse Field [0.0]
  Hyperuniform states of matter are characterized by anomalous suppression of long-wavelength density fluctuations. It is well-known that the transverse field Ising model shows a quantum phase transition (QPT) at zero temperature. Under the quantum effects of a transverse magnetic field, classical hyperuniform spin chains are expected to lose their hyperuniformity.
  arXiv  Detail & Related papers  (2020-12-11T18:21:50Z)
• A flux tunable superconducting quantum circuit based on Weyl semimetal MoTe2 [0.0]
  We present a transmon-like superconducting quantum intereference device (SQUID) SQUID consists of junctions made of Weyl semimetal Td-MoTe2 and superconducting leads niobium nitride (NbN) We demonstrate a JJ made of MoTe2 and a flux-tunable transmon-like circuit based on Weyl materials.
  arXiv  Detail & Related papers  (2020-10-27T07:24:39Z)
• Floquet engineering and simulating exceptional rings with a quantum spin system [6.746560936185888]
  Time-periodic driving in the form of coherent radiation provides powerful tool for the manipulation of topological materials or synthetic quantum matter. We propose a scheme to realize non-Hermitian semimetals exhibiting exceptional rings in the spectra through Floquet engineering.
  arXiv  Detail & Related papers  (2020-05-06T10:16:20Z)
• Universal non-adiabatic control of small-gap superconducting qubits [47.187609203210705]
  We introduce a superconducting composite qubit formed from two capacitively coupled transmon qubits. We control this low-frequency CQB using solely baseband pulses, non-adiabatic transitions, and coherent Landau-Zener interference. This work demonstrates that universal non-adiabatic control of low-frequency qubits is feasible using solely baseband pulses.
  arXiv  Detail & Related papers  (2020-03-29T22:48:34Z)
• Quantum emulation of coherent backscattering in a system of superconducting qubits [45.82374977939355]
  We use multi-pass Landau-Zener transitions at the avoided crossing of a highly-coherent superconducting qubit to emulate weak localization (WL) and universal conductance fluctuations (UCF) The higher coherence of this qubit enabled the realization of both effects, in contrast to earlier work arXiv:1204.6428, which successfully emulated UCF, but did not observe WL.
  arXiv  Detail & Related papers  (2019-12-28T17:11:53Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.