2012/01/02 by Sung-Guk Han, Beom Jun Kim
Computer Science · Physics and Astronomy · #Momentum (technical analysis) #Perturbation (astronomy) #Perturbation theory (quantum mechanics) #Quantum #Quantum many-body systems #Quantum-Dot Cellular Automata #Spectroscopy and Quantum Chemical Studies #Time evolution #Wave function #Wave packet #cond-mat.stat-mech
paper · pdf · doi:10.3938/jkps.60.665
published as JKPS Volume 60, Number 4 (2012), 665-668 · 4 pages, 2 figures (JKPS in press)
arxiv created 2012/01/02 · openalex publication_date 2012/02/01 · arxiv updated 2012/09/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We study the time-reversal dynamics of a tight-binding electron in the Watts-Strogatz (WS) small-world networks. The localized initial wave packet at time t = 0 diffuses as time proceeds until the time-reversal operation, together with the momentum perturbation of the strength η , is made at the reversal time T . The time irreversibility is measured by I = |Π( t = 2 T ) − Π( t = 0)|, where Π is the participation ratio gauging the extendedness of the wavefunction and for convenience, t is measured forward even after the time reversal. When η = 0, the time evolution after T makes the wavefunction at t = 2 T identical to the one at t = 0, and we find I = 0, implying a null irreversibility or a complete reversibility. On the other hand, as η is increased from zero, the reversibility becomes weaker, and we observe enhancement of the irreversibility. We find that I linearly increases with increasing η in the weakly-perturbed region, and that the irreversibility is much stronger in the WS network than in the local regular network.