Exotic Quantum Phenomena in Twisted Bilayer Graphene

• URL: http://arxiv.org/abs/2411.00854v1
• Date: Wed, 30 Oct 2024 13:55:54 GMT
• Title: Exotic Quantum Phenomena in Twisted Bilayer Graphene
• Authors: Giovanna Feraco, Wissem Boubaker, Petra Rudolf, Antonija Grubišić-Čabo,
• Abstract summary: Bilayer graphene twisted at the angle of 1.1deg exhibits ultra-flat moir'e superlattice bands that are a source of highly-tunable, exotic quantum phenomena. This article reviews the physics behind twisted bilayer graphene, focusing on moir'e physics and the importance of electronic (flat) band structure.
• Score: 0.0
• License:
• Abstract: Bilayer graphene twisted at the angle of about 1.1{\deg} better known as magic angle, exhibits ultra-flat moir\'e superlattice bands that are a source of highly-tunable, exotic quantum phenomena. Such phenomena, like superconductivity, correlated Mott-like insulating states and orbital ferromagnetism are driven by strong-correlation physics that defies classical theories. The inadequacy of such classical models and the lack of theoretical understanding of the recently observed exotic phenomena calls for revisiting the theory behind the material system and associating it with the observed behaviour. This article reviews the physics behind twisted bilayer graphene, focusing primarily on moir\'e physics and the importance of electronic (flat) band structure. In addition, this paper provides a brief overview of the emerging phenomena of correlated insulating states, superconductivity and orbital ferromagnetism. Finally, the most recent developments in controlling the interaction-driven states and tuning the electronic interactions are presented.

Related papers

• Probing the magnetic origin of the pseudogap using a Fermi-Hubbard quantum simulator [30.29758729899544]
  In strongly correlated materials, interacting electrons are entangled and form collective quantum states. Superconductivity emerges at low doping out of an unusual pseudogap'' metallic state above the critical temperature. We use a quantum gas microscope Fermi-Hubbard simulator to explore a wide range of doping levels and temperatures.
  arXiv  Detail & Related papers  (2024-12-23T18:58:01Z)
• Visualizing Dynamics of Charges and Strings in (2+1)D Lattice Gauge Theories [103.95523007319937]
  We study the dynamics of local excitations in a lattice of superconducting qubits. For confined excitations, the magnetic field induces a tension in the string connecting them. Our method allows us to experimentally image string dynamics in a (2+1)D LGT.
  arXiv  Detail & Related papers  (2024-09-25T17:59:05Z)
• Nonlinear dynamical Casimir effect and Unruh entanglement in waveguide QED with parametrically modulated coupling [83.88591755871734]
  We study theoretically an array of two-level qubits moving relative to a one-dimensional waveguide. When the frequency of this motion approaches twice the qubit resonance frequency, it induces parametric generation of photons and excitation of the qubits. We develop a comprehensive general theoretical framework that incorporates both perturbative diagrammatic techniques and a rigorous master-equation approach.
  arXiv  Detail & Related papers  (2024-08-30T15:54:33Z)
• Directly imaging spin polarons in a kinetically frustrated Hubbard system [0.0]
  Magnetic polarons arise from interplay between kinetic energy of doped charge carriers and superexchange spin interactions. Here we image itinerant spin polarons in a triangular lattice Hubbard system realised with ultracold atoms. In contrast, around a charge dopant we find ferromagnetic correlations, a manifestation of the elusive Nagaoka effect.
  arXiv  Detail & Related papers  (2023-08-24T17:41:07Z)
• Magnetically mediated hole pairing in fermionic ladders of ultracold atoms [0.0]
  We report on the observation of hole pairing due to magnetic correlations in a quantum gas microscope setting. By engineering doped antiferromagnetic ladders with mixed-dimensional couplings we suppress Pauli blocking of holes at short length scales. We find a hole-hole binding energy on the order of the superexchange energy, and, upon increased doping, we observe spatial structures in the pair distribution, indicating repulsion between bound hole pairs.
  arXiv  Detail & Related papers  (2022-03-18T15:54:32Z)
• Higher-order topological quantum paramagnets [0.0]
  Quantum paramagnets are strongly-correlated phases of matter where competing interactions frustrate magnetic order down to zero temperature. In certain cases, quantum fluctuations induce instead topological order, supporting, in particular, fractionalized quasi-particle excitations. We show how magnetic frustration can also give rise to higher-order topological properties.
  arXiv  Detail & Related papers  (2021-07-21T14:47:32Z)
• Topological photonics on superconducting quantum circuits with parametric couplings [1.5315375015702]
  Topological phases of matter is an exotic phenomena in modern condense matter physics. Topological photonics emerges as a rapid growing research field. We review theoretical and experimental advances of topological photonics on superconducting quantum circuits.
  arXiv  Detail & Related papers  (2021-02-01T14:31:17Z)
• Spin Entanglement and Magnetic Competition via Long-range Interactions in Spinor Quantum Optical Lattices [62.997667081978825]
  We study the effects of cavity mediated long range magnetic interactions and optical lattices in ultracold matter. We find that global interactions modify the underlying magnetic character of the system while introducing competition scenarios. These allow new alternatives toward the design of robust mechanisms for quantum information purposes.
  arXiv  Detail & Related papers  (2020-11-16T08:03:44Z)
• Quantum Hall phase emerging in an array of atoms interacting with photons [101.18253437732933]
  Topological quantum phases underpin many concepts of modern physics. Here, we reveal that the quantum Hall phase with topological edge states, spectral Landau levels and Hofstadter butterfly can emerge in a simple quantum system. Such systems, arrays of two-level atoms (qubits) coupled to light being described by the classical Dicke model, have recently been realized in experiments with cold atoms and superconducting qubits.
  arXiv  Detail & Related papers  (2020-03-18T14:56:39Z)
• Theoretical methods for ultrastrong light-matter interactions [91.3755431537592]
  This article reviews theoretical methods developed to understand cavity quantum electrodynamics in the ultrastrong-coupling regime. The article gives a broad overview of the recent progress, ranging from analytical estimate of ground-state properties to proper computation of master equations. Most of the article is devoted to effective models, relevant for the various experimental platforms in which the ultrastrong coupling has been reached.
  arXiv  Detail & Related papers  (2020-01-23T18:09:10Z)
• Quantum decoherence by Coulomb interaction [58.720142291102135]
  We present an experimental study of the Coulomb-induced decoherence of free electrons in a superposition state in a biprism electron interferometer close to a semiconducting and metallic surface. The results will enable the determination and minimization of specific decoherence channels in the design of novel quantum instruments.
  arXiv  Detail & Related papers  (2020-01-17T04:11:44Z)

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.