Arrested phase separation in double-exchange models: machine-learning enabled large-scale simulation

• URL: http://arxiv.org/abs/2105.08221v1
• Date: Tue, 18 May 2021 01:30:23 GMT
• Title: Arrested phase separation in double-exchange models: machine-learning enabled large-scale simulation
• Authors: Puhan Zhang, Gia-Wei Chern
• Abstract summary: We present large-scale dynamical simulations of electronic phase separation in the single-band double-exchange model. We uncover an intriguing correlation-induced freezing behavior as doped holes are segregated from half-filled insulating background during equilibration.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We present large-scale dynamical simulations of electronic phase separation in the single-band double-exchange model based on deep-learning neural-network potentials trained from small-size exact diagonalization solutions. We uncover an intriguing correlation-induced freezing behavior as doped holes are segregated from half-filled insulating background during equilibration. While the aggregation of holes is stabilized by the formation of ferromagnetic clusters through Hund's coupling between charge carriers and local magnetic moments, this stabilization also creates confining potentials for holes when antiferromagnetic spin-spin correlation is well developed in the background. The dramatically reduced mobility of the self-trapped holes prematurely disrupts further growth of the ferromagnetic clusters, leading to an arrested phase separation. Implications of our findings for phase separation dynamics in materials that exhibit colossal magnetoresistance effect are discussed.

Related papers

• Collective Dissipation of Oscillator Dipoles Strongly Coupled to 1-D Electromagnetic Reservoirs [0.0]
  We study the collective dissipative dynamics of dipoles modeled as harmonic oscillators coupled to 1-D electromagnetic reservoirs. At weak coupling, apart from recovering the dynamics expected from a Markovian Lindblad master equation, we also obtain non-Markovian effects for spatially separated two-level emitters.
  arXiv  Detail & Related papers  (2024-11-03T19:22:58Z)
• 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)
• Momentum-selective pair creation of spin excitations in dipolar bilayers [0.0]
  We study the temporal growth and spatial propagation of quantum correlations in a two-dimensional bilayer realising a spin-1/2 quantum XXZ model with couplings mediated by long-range and anisotropic dipolar interactions. The predicted behavior remains observable at very low filling fractions, making it accessible in state-of-the-art experiments with Rydberg atoms, magnetic atoms, and polar molecule arrays.
  arXiv  Detail & Related papers  (2023-02-17T18:50:13Z)
• Slow semiclassical dynamics of a two-dimensional Hubbard model in disorder-free potentials [77.34726150561087]
  We show that introduction of harmonic and spin-dependent linear potentials sufficiently validates fTWA for longer times. In particular, we focus on a finite two-dimensional system and show that at intermediate linear potential strength, the addition of a harmonic potential and spin dependence of the tilt, results in subdiffusive dynamics.
  arXiv  Detail & Related papers  (2022-10-03T16:51:25Z)
• Probing dynamics of a two-dimensional dipolar spin ensemble using single qubit sensor [62.997667081978825]
  We experimentally investigate individual spin dynamics in a two-dimensional ensemble of electron spins on the surface of a diamond crystal. We show that this anomalously slow relaxation rate is due to the presence of strong dynamical disorder. Our work paves the way towards microscopic study and control of quantum thermalization in strongly interacting disordered spin ensembles.
  arXiv  Detail & Related papers  (2022-07-21T18:00:17Z)
• Rotating Majorana Zero Modes in a disk geometry [75.34254292381189]
  We study the manipulation of Majorana zero modes in a thin disk made from a $p$-wave superconductor. We analyze the second-order topological corner modes that arise when an in-plane magnetic field is applied. We show that oscillations persist even in the adiabatic phase because of a frequency independent coupling between zero modes and excited states.
  arXiv  Detail & Related papers  (2021-09-08T11:18:50Z)
• Chemical tuning of spin clock transitions in molecular monomers based on nuclear spin-free Ni(II) [52.259804540075514]
  We report the existence of a sizeable quantum tunnelling splitting between the two lowest electronic spin levels of mononuclear Ni complexes. The level anti-crossing, or magnetic clock transition, associated with this gap has been directly monitored by heat capacity experiments. The comparison of these results with those obtained for a Co derivative, for which tunnelling is forbidden by symmetry, shows that the clock transition leads to an effective suppression of intermolecular spin-spin interactions.
  arXiv  Detail & Related papers  (2021-03-04T13:31:40Z)
• Effects of the dynamical magnetization state on spin transfer [68.8204255655161]
  We show that the complex interactions between the spin-polarized electrons and the dynamical states of the local spins can be decomposed into separate processes. Our results suggest that exquisite control of spin transfer efficiency and of the resulting dynamical magnetization states may be achievable.
  arXiv  Detail & Related papers  (2021-01-21T22:12:03Z)
• Coupling a mobile hole to an antiferromagnetic spin background: Transient dynamics of a magnetic polaron [0.0]
  In this work, we use a cold-atom quantum simulator to directly observe the formation dynamics and subsequent spreading of individual magnetic polarons. Measuring the density- and spin-resolved evolution of a single hole in a 2D Hubbard insulator with short-range antiferromagnetic correlations reveals fast initial delocalization and a dressing of the spin background. Our work enables the study of out-of-equilibrium emergent phenomena in the Fermi-Hubbard model, one dopant at a time.
  arXiv  Detail & Related papers  (2020-06-11T17:59:54Z)
• Entanglement dynamics in dissipative photonic Mott insulators [62.997667081978825]
  In spite of particle losses the quantum entanglement propagation exhibits a ballistic character with propagation speeds related to the differerent quasiparticles that are involved in the dynamics. Our analysis reveals that photon dissipation has a strikingly asymmetric behavior in the two configurations with a much more dramatic role on the holon entanglement propagation than for the doublon case.
  arXiv  Detail & Related papers  (2020-04-27T15:48:24Z)
• Interplay of phase separation and itinerant magnetism for correlated few fermions in a double-well [0.0]
  We explore the stability of the phase separation phenomenon in few-fermion spin-$1/2$ systems confined in a double-well potential. Our results imply an intricate relation between the phenomena of phase separation and ferromagnetism that lies beyond the view of the Stoner instability.
  arXiv  Detail & Related papers  (2020-01-15T13:34:51Z)

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.