An On/Off Berry Phase Switch in Circular Graphene Resonators
Abstract
The phase of a quantum state may not return to its original value after the system's parameters cycle around a closed path; instead, the wavefunction may acquire a measurable phase difference called the Berry phase. Berry phases typically have been accessed through interference experiments. Here, we demonstrate an unusual Berry-phase-induced spectroscopic feature: a sudden and large increase in the energy of angular-momentum states in circular graphene p-n junction resonators when a small critical magnetic field is reached. This behavior results from turning on a -Berry phase associated with the topological properties of Dirac fermions in graphene. The Berry phase can be switched on and off with small magnetic field changes on the order of 10 mT, potentially enabling a variety of optoelectronic graphene device applications.
Keywords
Cite
@article{arxiv.1705.11117,
title = {An On/Off Berry Phase Switch in Circular Graphene Resonators},
author = {Fereshte Ghahari and Daniel Walkup and Christopher Gutiérrez and Joaquin F. Rodriguez-Nieva and Yue Zhao and Jonathan Wyrick and Fabian D. Natterer and William G. Cullen and Kenji Watanabe and Takashi Taniguchi and Leonid S. Levitov and Nikolai B. Zhitenev and Joseph A. Stroscio},
journal= {arXiv preprint arXiv:1705.11117},
year = {2017}
}