Investigation of continuous-time quantum walk by using Krylov subspace-Lanczos algorithm M. A. Jafarizadeh, R. Sufiani, S. Salimi and S. Jafarizadeh Eur. Phys. J. B, 59 2 (2007) 199-216 Published online: 17 October 2007 DOI: 10.1140/epjb/e2007-00281-5