Particle injection into a chain: decoherence versus relaxation for Hermitian and non-Hermitian dynamics
| Autor: | Gebhard, F., Muenster, K. zu, Ren, J., Sedlmayr, N., Sirker, J., Ziebarth, B. |
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| Rok vydání: | 2011 |
| Předmět: | |
| Zdroj: | Ann. Phys. (Berlin) 524, 286 (2012) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1002/andp.201100287 |
| Popis: | We investigate a model system for the injection of fermionic particles from filled source sites into an empty chain. We study the ensuing dynamics for Hermitian as well as for non-Hermitian time evolution where the particles cannot return to the bath sites (quantum ratchet). A non-homogeneous hybridization between bath and chain sites permits transient currents in the chain. Non-interacting particles show decoherence in the thermodynamic limit: the average particle number and the average current density in the chain become stationary for long times, whereas the single-particle density matrix displays large fluctuations around its mean value. Using the numerical time-dependent density-matrix renormalization group ($t$-DMRG) method we demonstrate, on the other hand, that sizable density-density interactions between the particles introduce relaxation which is by orders of magnitudes faster than the decoherence processes. Comment: 22 pages, 16 figures |
| Databáze: | arXiv |
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