Non-Hermitian quantum rings
Abstract
We investigate the spectral and dynamical properties of a quantum particle constrained on a ring threaded by a magnetic flux in presence of a complex (non-Hermitian) potential. For a static magnetic flux, the quantum states of the particle on the ring can be mapped into the Bloch states of a complex crystal, and magnetic flux tuning enables to probe the spectral features of the complex crystal, including the appearance of exceptional points. For a time-varying (linearly-ramped) magnetic flux, Zener tunneling among energy states is realized owing to the induced electromotive force. As compared to the Hermitian case, striking effects are observed in the non-Hermitian case, such as a highly asymmetric behavior of particle motion when reversing the direction of the magnetic flux and field-induced delayed transparency.
Cite
@article{arxiv.1312.4693,
title = {Non-Hermitian quantum rings},
author = {Stefano Longhi},
journal= {arXiv preprint arXiv:1312.4693},
year = {2015}
}
Comments
9 pages, 5 figures; to appear in the Phys. Rev. A