Emergence of Diverse Topological States in Ge Doped MnBi2Te4

• URL: http://arxiv.org/abs/2505.22348v1
• Date: Wed, 28 May 2025 13:30:31 GMT
• Title: Emergence of Diverse Topological States in Ge Doped MnBi2Te4
• Authors: Zhijian Shi, Shengjie Xu, Jianfeng Wang, Yi Du, Weichang Hao,
• Abstract summary: We investigate the band evolution and topological phase diagram with doping concentration from MTI MnBi2Te4 to strong topological insulator GeBi2Te4.<n>By employing a band momentum mapping method, besides the known MTI phase, remarkably, we find two classes of magnetic Dirac semimetal phases at antiferromagnetic state.<n>The trivial state can be tuned into a Weyl phase with two coexisting band inversions and extraordinarily long Fermi arcs by a small strain.
• Score: 35.56261187819994
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: As an ideal platform for studying interplays between symmetry, topology and magnetism, the magnetic topological insulator (MTI) MnBi2Te4 has attracted extensive attentions. However, its strong n-type intrinsic defects hinder the realizations of exotic phenomena. Stimulated by recent discoveries that Ge doping can efficiently tune the position of Fermi level, here we systematically investigate the band evolution and topological phase diagram with doping concentration from MTI MnBi2Te4 to strong topological insulator GeBi2Te4. Different from magnetically doped Bi2Se3, the topology here is determined by competition of two band inversions arising from band folding of two time-reversal invariant momenta between antiferromagnetic and nonmagnetic/ferromagnetic unit cells. By employing a band momentum mapping method, besides the known MTI phase, remarkably, we find two classes of magnetic Dirac semimetal phases at antiferromagnetic state, two classes of Weyl semimetal phases at ferromagnetic state, and an intermediate trivial state at different doping regions. Interestingly, the trivial state can be tuned into a Weyl phase with two coexisting band inversions and extraordinarily long Fermi arcs by a small strain. Our work reveals diverse topological states with intrinsic quantum phenomena can be achieved with great potential for designing future electronic devices.

Related papers

• Observation of Magnetic Devil's Staircase-Like Behavior in Quasiperiodic Qubit Lattices [55.2480439325792]
  devil's staircase (DS) phenomenon is a fractal response of magnetization to external fields.<n>We uncover a wealth of abrupt magnetic transitions driven by increasing external magnetic fields within a simple yet effective Ising-model framework.<n>Our results challenge the prevailing view that DS behavior is limited to periodic systems.
  arXiv  Detail & Related papers  (2025-07-24T21:39:06Z)
• Emergent Kitaev materials in synthetic Fermi-Hubbard bilayers [49.1574468325115]
  Bond-directional spin-spin interactions in a Fermi-Hubbard bilayer can be realized with ultracold fermions in Raman optical lattices.<n>We analyze the Fermi-liquid and Mott-insulating phases, highlighting a correspondence between Dirac and Majorana quasi-particles.<n>Our results establish that cold-atom quantum simulators based on Raman optical lattices can be a playground for extended Kitaev models.
  arXiv  Detail & Related papers  (2025-04-22T10:07:56Z)
• Probing Quantum Anomalous Hall States in Twisted Bilayer WSe2 via Attractive Polaron Spectroscopy [2.190598186971745]
  We report the first optical detection of quantum anomalous Hall (QAH) states in twisted WSe2 homobilayer (tWSe2)<n>Our findings position tWSe2 as a highly versatile, stable, and optically addressable platform for investigating topological order and strong correlations in two-dimensional landscapes.
  arXiv  Detail & Related papers  (2025-04-15T18:00:03Z)
• Controllable and Continuous Quantum Phase Transitions in Intrinsic Magnetic Topological Insulator [50.54133633499971]
  We study the intrinsic magnetic topological material MnBi2Te4 in which the heavy n-type doping features are strongly suppressed.<n>Based on angle-resolved photoemission spectroscopy, transport measurements, and first-principles calculations, we reveal two magnetism-induced TPTs.<n>Our work paves the way for the realization of intrinsic magnetic topological states in MnBi2Te4 family and provides an ideal platform for achieving controllable and continuous TPTs.
  arXiv  Detail & Related papers  (2025-03-08T03:46:54Z)
• Transport properties and quantum phase transitions in one-dimensional superconductor-ferromagnetic insulator heterostructures [44.99833362998488]
  We propose a one-dimensional electronic nanodevice inspired in recently fabricated semiconductor-superconductor-ferromagnetic insulator hybrids. We show that the device can be tuned across spin- and fermion parity-changing QPTs by adjusting the FMI layer length orange and/or by applying a global backgate voltage. Our findings suggest that these effects are experimentally accessible and offer a robust platform for studying quantum phase transitions in hybrid nanowires.
  arXiv  Detail & Related papers  (2024-10-18T22:25:50Z)
• Antiferromagnetic Quantum Anomalous Hall Effect Modulated by Spin Flips and Flops [23.17305544412557]
  We fabricate a device of 7-septuple-layer MnBi2Te4 covered with AlOx capping layer. We uncover a cascade of quantum phase transitions that can be attributed to the influence of spin configurations on charge transport. The versatile tunability of the quantum anomalous Hall effect in MnBi2Te4 paves the way for potential applications in topological antiferromagnetic spintronics.
  arXiv  Detail & Related papers  (2024-05-14T15:08:07Z)
• Non-volatile Electric Control of Magnetic and Topological Properties of MnBi2Te4 Thin Films [66.02797153096846]
  We propose a mechanism to control the magnetic properties of topological quantum material (TQM) by using magnetoelectric coupling. This mechanism uses a heterostructure of TQM with two-dimensional (2D) ferroelectric material.
  arXiv  Detail & Related papers  (2022-12-29T14:51:05Z)
• 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)
• Insights on magnon topology and valley-polarization in 2D bilayer quantum magnets [0.0]
  Two-dimensional (2D) bilayer quantum magnets are gaining increasing attention due to their intriguing stacking-dependent magnetism. Despite the substantial research on these materials, their topological features remain widely unexplored to date. The present study comprehensively investigates the magnon topology and magnon valley-polarization in honeycomb bilayers with collinear magnetic order.
  arXiv  Detail & Related papers  (2020-10-16T20:40:53Z)
• Experimental evidence for topological phases in the magnetoconductance of 2DEG-based hybrid junctions [0.0]
  Majorana phases emerge as quantized plateaus in the magnetoconductance of hybrid junctions based on two-dimensional electron gases (2DEG) under fully out-of-plane magnetic fields. We report on the experimental observation of such topological phases in Josephson junctions, based on In0.75Ga0.25As 2DEG, by sweeping out-of-plane magnetic fields of as small as 0 B(mT) 100.
  arXiv  Detail & Related papers  (2020-07-04T09:53:13Z)

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.