Trojan Quantum Walks

  • Henrique S. Ghizoni
  • Edgard P. M. AmorimEmail author
Atomic Physics


We investigate the transport properties and entanglement between spin and position of one-dimensional quantum walks starting from a qubit over position states following a delta-like (local state) and Gaussian (delocalized state) distributions. We find out that if the initial state is delocalized enough and a NOT gate reflects this state backwards, then the interference pattern extinguishes the position dispersion without preventing the propagation of the state. This effect allows the creation of a Trojan wave packet, a non-spreading and non-stationary double-peak quantum state.


Spreading Entanglement Gaussian states Quantum walks 



HSG and EPMA thank Janice Longo for her careful reading of the manuscript.

Funding Information

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001.


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Copyright information

© Sociedade Brasileira de Física 2019

Authors and Affiliations

  1. 1.Departamento de FísicaUniversidade do Estado de Santa CatarinaJoinvilleBrazil

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