Construction of topological quantum magnets from atomic spins on surfaces

Abstract

Artificial quantum systems have emerged as indispensable platforms to realize exotic topological matter in a well-controlled manner. Here, we demonstrate topological quantum Heisenberg spin lattices, engineered with spin chains and two-dimensional spin arrays using spin 1/2 atoms on insulating films in a scanning tunnelling microscope (STM). We engineered with atomic precision both topological and trivial phases of the quantum spin model, realizing first- and second-order topological quantum magnets. Their many-body excitations were probed by single-atom electron spin resonance with ultrahigh energy resolution. The atomically-localized magnetic field of the STM tip allows us to directly visualize various topological bound modes including topological edge states, topological defects, and higher-order corner modes. Our results provide an important bottom-up approach to simulating exotic quantum many-body phases of interacting spins.

Nature Nanotechnology (2024)

References in corpus (12)

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Cited by in corpus (12)

• Conformational tuning of magnetic interactions in coupled nanographenes
• Direct electrical access to the spin manifolds of individual monovalent lanthanide atoms
• Single-shot readout of the nuclear spin of an on-surface atom
• Higher-order Topological States in Chiral Split Magnons of Honeycomb Altermagnets
• Observation of average topological phase in disordered Rydberg atom array
• Electrically tunable quantum interference of atomic spins on surfaces
• Hamiltonian Learning of Triplon Excitations in an Artificial Nanoscale Molecular Quantum Magnet
• Hamiltonian-learning quantum magnets with non-local impurity tomography
• Local dynamics and detection of topology in spin-1 chains
• Phase diagram of the J1-J2 Heisenberg second-order topological quantum magnet
• Two topological phases in exchange alternating spin-1 nanographene chains
• Theory of Electron Spin Resonance Scanning Tunneling Microscopy: The First Decade