PHYSICS LETTERS A, vol.380, no.29-30, pp.2260-2264, 2016 (SCI-Expanded)
Wannier-Stark ladder in a PT symmetric system is generally complex that leads to amplified/damped Bloch oscillation. We show that a non-amplified wave packet oscillation with very large amplitude can be realized in a non-Hermitian tight binding lattice if certain conditions are satisfied. We show that pseudo PT symmetry guarantees the reality of the quasi energy spectrum in our system. (C) 2016 Elsevier B.V. All rights reserved.