Quantum transport and spin dynamics on shearless tori

K. Kudo, T. S. Monteiro

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


We investigate quantum dynamics in phase-space regions containing "shearless tori." We show that the properties of these peculiar classical phase-space structures-important to the dynamics of tokamaks-may be exploited for quantum information applications. In particular we show that shearless tori permit the nondispersive transmission of localized wave packets. The quantum many-body Hamiltonian of a Heisenberg ferromagnetic spin chain, subjected to an oscillating magnetic field, can be reduced to a classical one-body "image" dynamical system which is the well-studied Harper map. The Harper map belongs to a class of Hamiltonian systems (nontwist maps) which contain shearless tori. We show that a variant with sinusoidal time driving "driven Harper model" produces shearless tori which are especially suitable for quantum state transfer. The behavior of the concurrence is investigated as an example.

Original languageEnglish
Article number055203
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Issue number5
Publication statusPublished - 2008 May 29
Externally publishedYes

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics


Dive into the research topics of 'Quantum transport and spin dynamics on shearless tori'. Together they form a unique fingerprint.

Cite this