English

Effect of quantum entanglement on Aharonov-Bohm oscillations, spin-polarized transport and current magnification effect

Mesoscale and Nanoscale Physics 2009-11-07 v1

Abstract

We present a simple model of transmission across a metallic mesoscopic ring. In one of its arm an electron interacts with a single magnetic impurity via an exchange coupling. We show that entanglement between electron and spin impurity states leads to reduction of Aharonov-Bohm oscillations in the transmission coefficient. The spin-conductance is asymmetric in the flux reversal as opposed to the two probe electrical conductance which is symmetric. In the same model in contradiction to the naive expectation of a current magnification effect, we observe enhancement as well as the suppression of this effect depending on the system parameters. The limitations of this model to the general notion of dephasing or decoherence in quantum systems are pointed out.

Keywords

Cite

@article{arxiv.cond-mat/0107080,
  title  = {Effect of quantum entanglement on Aharonov-Bohm oscillations, spin-polarized transport and current magnification effect},
  author = {A. M. Jayannavar},
  journal= {arXiv preprint arXiv:cond-mat/0107080},
  year   = {2009}
}

Comments

Talk presented at the International Discussion Meeting on Mesoscopic and Disordered systems, December, 2000, at IISc Bangalore 17 pages, 8figures