Engineering open-shell extended edge states in chiral graphene nanoribbons on MgO

• URL: http://arxiv.org/abs/2406.03927v1
• Date: Thu, 6 Jun 2024 10:08:59 GMT
• Title: Engineering open-shell extended edge states in chiral graphene nanoribbons on MgO
• Authors: Amelia Domínguez-Celorrio, Leonard Edens, Sofía Sanz, Manuel Vilas-Varela, Jose Martinez-Castro, Diego Peña, Véronique Langlais, Thomas Frederiksen, José I. Pascual, David Serrate,
• Abstract summary: We show that the edges of narrow chiral graphene nanoribbons (GNRs) over MgO monolayers on Ag(001) can host integer charge and spin-1/2 frontier states. We envisage that GNRs supported by thin insulating films can be used as tailor-made active elements in quantum sensing and quantum information processing.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Graphene nanostructures are a promising platform for engineering electronic states with tailored magnetic and quantum properties. Synthesis strategies on metallic substrates have made it possible to manufacture atomically precise nanographenes with controlled size, shape and edge geometry. In these nanographenes, finite spin magnetic moment can arise as a result of many-body interactions in molecular orbitals with $\pi$-conjugated character and subject to strong spatial confinement, for example at the zig-zag edges. However, owing to the mixing of the molecular orbitals and metallic states from the catalysing substrate, most of their expected quantum phenomenology is severely hindered. The use of in-situ ultra-thin decoupling layers can impede nanographene-metal hybridization and facilitate the expression of predicted properties. Here we show that the edges of narrow chiral graphene nanoribbons (GNRs) over MgO monolayers on Ag(001) can host integer charge and spin-1/2 frontier states. The electron occupation varies with the GNR length, which alternates even or odd number of electrons, thus resulting correspondingly in a non-magnetic closed-shell state or an open-shell paramagnetic system. For the latter, we found the spectral fingerprint of a narrow Coulomb correlation gap. Charged states, up to 19 additional electrons, were identified by comparing mean-field Hubbard (MFH) simulations of the density of states with experimental maps of the discretized molecular orbitals acquired with a scanning tunnelling microscope (STM). In consideration of the length-dependent magnetic moment and the discrete nature of the electronic structure, we envisage that GNRs supported by thin insulating films can be used as tailor-made active elements in quantum sensing and quantum information processing.

Related papers

• Nonlinear Tripartite Coupling of Single Electrons on Solid Neon with Magnons in a Hybrid Quantum System [0.32885740436059047]
  Coherent nonlinear tripartite interactions are critical for advancing quantum simulation and information processing in hybrid quantum systems. Here, we predict a tripartite coupling mechanism in a hybrid setup comprising a single electron trapped on a solid neon surface and a nearby micromagnet. Thanks to the large spatial extent of the electron zero-point motion, we show that it is possible to obtain a tunable and strong spin-magnon-motion coupling at the single quantum level.
  arXiv  Detail & Related papers  (2025-03-11T16:22:44Z)
• Electron-Electron Interactions in Device Simulation via Non-equilibrium Green's Functions and the GW Approximation [71.63026504030766]
  electron-electron (e-e) interactions must be explicitly incorporated in quantum transport simulation. This study is the first one reporting large-scale atomistic quantum transport simulations of nano-devices under non-equilibrium conditions.
  arXiv  Detail & Related papers  (2024-12-17T15:05:33Z)
• Spin Squeezing with Magnetic Dipoles [37.93140485169168]
  Entanglement can improve the measurement precision of quantum sensors beyond the shot noise limit. We take advantage of the magnetic dipole-dipole interaction native to most neutral atoms to realize spin-squeezed states. We achieve 7.1 dB of metrologically useful squeezing using the finite-range spin exchange interactions in an erbium quantum gas microscope.
  arXiv  Detail & Related papers  (2024-11-11T18:42:13Z)
• Kinetic magnetism and stripe order in the antiferromagnetic bosonic ${t-J}$ model [0.0]
  We explore the strong coupling limit of doped emphbosonic quantum magnets, specifically the antiferromagnetic (AFM) bosonic $t-J$ model. As doping increases, a transition occurs to a partially-polarized ferromagnetic (FM) phase, driven by the motion of mobile bosonic charge carriers forming Nagaoka polarons. These findings shed new light on the role of particle statistics in strongly correlated many-body systems, revealing connections tomagnet formation and the physics of kinetic (i.e., Nagaoka-type) ferromagnetism.
  arXiv  Detail & Related papers  (2024-10-01T17:50:10Z)
• An NV- center in magnesium oxide as a spin qubit for hybrid quantum technologies [1.2774526936067931]
  We identify a negative complex between a nitrogen interstitial and a magnesium vacancy in MgO with favorable electronic and optical properties. We show that this NV- center has stable triplet ground and excited states, with singlet shelving states enabling optical readout. We propose that the favorable properties of the NV- defect, along with the technological maturity of MgO, could enable hybrid classical-quantum applications.
  arXiv  Detail & Related papers  (2024-08-30T20:32:40Z)
• Ferrimagnetism of ultracold fermions in a multi-band Hubbard system [34.95884242542007]
  We report on signatures of a ferrimagnetic state realized in a Lieb lattice at half-filling. We demonstrate its robustness when increasing repulsive interactions from the non-interacting to the Heisenberg regime. Our work paves the way towards exploring exotic phases in related multi-orbital models such as quantum spin liquids in kagome lattices and heavy fermion behavior in Kondo models.
  arXiv  Detail & Related papers  (2024-04-26T17:33:26Z)
• Spin decoherence in VOPc@graphene nanoribbon complexes [5.691318972818067]
  Carbon nanoribbon or nanographene qubit arrays can facilitate quantum-to-quantum transduction between light, charge, and spin. We study spin decoherence due to coupling with a surrounding nuclear spin bath of an electronic molecular spin of a vanadyl phthalocyanine (VOPc) molecule integrated on an armchair-edged graphene nanoribbon (GNR) We find that the decoherence time $T$ is anisotropic with respect to magnetic field orientation and determined only by nuclear spins on VOPc and GNR.
  arXiv  Detail & Related papers  (2023-07-31T04:55:05Z)
• Dy adatom on MgO(001) substrate: DFT+U(HIA) study [75.7995398006171]
  The electronic structure and magnetism of individual Dy atom adsorbed on the MgO(001) substrate is investigated. Our studies can provide a viable route for further investigation and prediction of the rare-earth single atom magnets.
  arXiv  Detail & Related papers  (2023-06-14T10:20:02Z)
• Scanning NV magnetometry of focused-electron-beam-deposited cobalt nanomagnets [0.0]
  Focused-electron-beam-induced deposition is a promising technique for patterning nanomagnets for spin qubit control in a single step. We fabricate cobalt nanomagnets in such a process, obtaining cobalt contents and saturation magnetizations comparable to or higher than those typically obtained using electron-beam lithography.
  arXiv  Detail & Related papers  (2023-06-11T11:13:02Z)
• 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)
• Exploring the magnetic properties of individual barcode nanowires using wide-field diamond microscopy [11.075031308210317]
  Barcode magnetic nanowires have attracted significant attention, particularly in the field of bioengineering. We investigated the characterization of magnetic nanowires at room temperature under ambient conditions. We could extract critical magnetic properties, such as the saturation magnetization and coercivity, of single nanowires.
  arXiv  Detail & Related papers  (2023-02-21T09:20:59Z)
• Protected Topological Nodal Ring Semimetal in Graphene [0.0]
  We introduce a topological nodal ring semimetal in graphene with a quantized quantum Hall response. The system may have applications in nano-electronics and in quantum mechanical entanglement applied to band theory.
  arXiv  Detail & Related papers  (2022-11-09T15:15:39Z)
• Spin Current Density Functional Theory of the Quantum Spin-Hall Phase [59.50307752165016]
  We apply the spin current density functional theory to the quantum spin-Hall phase. We show that the explicit account of spin currents in the electron-electron potential of the SCDFT is key to the appearance of a Dirac cone.
  arXiv  Detail & Related papers  (2022-08-29T20:46:26Z)
• Quantum phase transition in magnetic nanographenes on a lead superconductor [21.166883497183687]
  Quantum spins are proposed to host exotic interactions with superconductivity. Magnetic nanographenes have been proven to host intrinsic quantum magnetism due to their negligible spin orbital coupling and crystal field splitting. We fabricate three atomically precise nanographenes with the same magnetic ground state of spin S=1/2 on Pb (111) through engineering sublattice imbalance in graphene honeycomb lattice.
  arXiv  Detail & Related papers  (2022-07-12T04:52:02Z)
• The remarkable prospect for quantum-dot-coupled tin qubits in silicon [0.0]
  Tin is isoelectronic with silicon, so electrons can easily shuttle from one Sn atom to another to propagate quantum information. A hyperfine-induced electro-nuclear controlled-phase gate operation is predicted to be exceptionally resilient to charge/voltage noise.
  arXiv  Detail & Related papers  (2022-06-13T16:16:07Z)
• Relativistic aspects of orbital and magnetic anisotropies in the chemical bonding and structure of lanthanide molecules [60.17174832243075]
  We study the electronic and ro-vibrational states of heavy homonuclear lanthanide Er2 and Tm2 molecules by applying state-of-the-art relativistic methods. We were able to obtain reliable spin-orbit and correlation-induced splittings between the 91 Er2 and 36 Tm2 electronic potentials dissociating to two ground-state atoms.
  arXiv  Detail & Related papers  (2021-07-06T15:34:00Z)
• Demonstration of electron-nuclear decoupling at a spin clock transition [54.088309058031705]
  Clock transitions protect molecular spin qubits from magnetic noise. linear coupling to nuclear degrees of freedom causes a modulation and decay of electronic coherence. An absence of quantum information leakage to the nuclear bath provides opportunities to characterize other decoherence sources.
  arXiv  Detail & Related papers  (2021-06-09T16:23:47Z)
• 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)
• General quantum-mechanical solution for twisted electrons in a uniform magnetic field [68.8204255655161]
  A theory of twisted (and other structured) paraxial electrons in a uniform magnetic field is developed. The observable effect of a different behavior of relativistic Laguerre-Gauss beams with opposite directions of the orbital angular momentum penetrating from the free space into a magnetic field is predicted.
  arXiv  Detail & Related papers  (2020-05-13T16:35:10Z)
• Quantum coherent spin-electric control in a molecular nanomagnet at clock transitions [57.50861918173065]
  Electrical control of spins at the nanoscale offers architectural advantages in spintronics. Recent demonstrations of electric-field (E-field) sensitivities in molecular spin materials are tantalising. E-field sensitivities reported so far are rather weak, prompting the question of how to design molecules with stronger spin-electric couplings.
  arXiv  Detail & Related papers  (2020-05-03T09:27:31Z)

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.