Quantum walk on a graph of spins: magnetism and entanglement

• URL: http://arxiv.org/abs/2006.14883v1
• Date: Fri, 26 Jun 2020 09:32:57 GMT
• Title: Quantum walk on a graph of spins: magnetism and entanglement
• Authors: Kevissen Sellapillay and Alberto D. Verga
• Abstract summary: We introduce a model of a quantum walk on a graph in which a particle jumps between neighboring nodes and interacts with independent spins sitting on the edges. Entanglement propagates with the walker. We apply this model to the case of a one dimensional lattice, to investigate its magnetic and entanglement properties.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: We introduce a model of a quantum walk on a graph in which a particle jumps between neighboring nodes and interacts with independent spins sitting on the edges. Entanglement propagates with the walker. We apply this model to the case of a one dimensional lattice, to investigate its magnetic and entanglement properties. In the continuum limit, we recover a Landau-Lifshitz equation that describes the precession of spins. A rich dynamics is observed, with regimes of particle propagation and localization, together with spin oscillations and relaxation. Entanglement of the asymptotic states follows a volume law for most parameters (the coin rotation angle and the particle-spin coupling).

Related papers

• 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)
• Zig-zag dynamics in a Stern-Gerlach spin measurement [0.0]
  We visualize the trajectories following the Bohmian zig-zag dynamics. The corresponding trajectories exhibit a zig-zagging, as the result of the coupling between left- and right-handed electron states. Results clarify the different meanings of spin'' as a property of the wave function and as a random variable in the SternGerlach setup.
  arXiv  Detail & Related papers  (2023-11-22T14:04:22Z)
• Entanglement Generation and Decoherence in a Two-Qubit System Mediated by Relativistic Quantum Field [0.0]
  We study a toy model of a quantum entanglement generation between two spins (qubits) mediated by a relativistic free scalar field. Because of the associated particle creation into an open system, the quantum state of spins is partially decohered. We calculate various quantities such as spin correlations, entanglement entropies, mutual information and negativity, and study their behaviors in various limiting situations.
  arXiv  Detail & Related papers  (2022-11-17T10:05:02Z)
• Quantum vibrational mode in a cavity confining a massless spinor field [91.3755431537592]
  We analyse the reaction of a massless (1+1)-dimensional spinor field to the harmonic motion of one cavity wall. We demonstrate that the system is able to convert bosons into fermion pairs at the lowest perturbative order.
  arXiv  Detail & Related papers  (2022-09-12T08:21:12Z)
• Measurable fractional spin for quantum Hall quasiparticles on the disk [0.0]
  We study the spin of the localised quasiparticles of lowest-Landau-level quantum Hall states defined on a disk. Since it is related to the quadrupole moment of the quasiparticle charge distribution, it can be measured in an experiment.
  arXiv  Detail & Related papers  (2021-12-06T09:53:54Z)
• Dispersive readout of molecular spin qudits [68.8204255655161]
  We study the physics of a magnetic molecule described by a "giant" spin with multiple $d > 2$ spin states. We derive an expression for the output modes in the dispersive regime of operation. We find that the measurement of the cavity transmission allows to uniquely determine the spin state of the qudits.
  arXiv  Detail & Related papers  (2021-09-29T18:00:09Z)
• Achieving spin-squeezed states by quench dynamics in a quantum chain [0.0]
  We study the time evolution of spin squeezing in the one-dimensional spin-1/2 XY model subject to a sudden quantum quench of a transverse magnetic field. Our analysis, based on exact results for the model, reveals that by a proper choice of protocol, a quantum quench from an unsqueezed state can create spin squeezed nonequilibrium states.
  arXiv  Detail & Related papers  (2021-08-31T12:48:52Z)
• Spin squeezing from bilinear spin-spin interactions: two simple theorems [0.0]
  We demonstrate two simple theorems about squeezing induced by bilinear spin-spin interactions. We show that squeezing captures the first form of quantum correlations.
  arXiv  Detail & Related papers  (2021-06-14T14:36:02Z)
• Position and spin in relativistic quantum mechanics [68.8204255655161]
  The position and spin operators in the Foldy-Wouthuysen representation are quantum-mechanical counterparts of the classical position and spin variables. The spin-orbit interaction does not exist for a free particle if the conventional operators of the orbital angular momentum and the rest-frame spin are used.
  arXiv  Detail & Related papers  (2020-03-14T07:49:40Z)
• Zitterbewegung and Klein-tunneling phenomena for transient quantum waves [77.34726150561087]
  We show that the Zitterbewegung effect manifests itself as a series of quantum beats of the particle density in the long-time limit. We also find a time-domain where the particle density of the point source is governed by the propagation of a main wavefront. The relative positions of these wavefronts are used to investigate the time-delay of quantum waves in the Klein-tunneling regime.
  arXiv  Detail & Related papers  (2020-03-09T21:27:02Z)
• Spin current generation and control in carbon nanotubes by combining rotation and magnetic field [78.72753218464803]
  We study the quantum dynamics of ballistic electrons in rotating carbon nanotubes in the presence of a uniform magnetic field. By suitably combining the applied magnetic field intensity and rotation speed, one can tune one of the currents to zero while keeping the other one finite, giving rise to a spin current generator.
  arXiv  Detail & Related papers  (2020-01-20T08:54:56Z)

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.