An on/off Berry phase switch in circular graphene resonators
- National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States)
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Harvard Univ., Cambridge, MA (United States)
- National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Univ. of Maryland, College Park, MD (United States); South Univ. of Science and Technology of China, Shenzhen (China)
- National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
- National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States); Ecole Polytechnique Federale Lausanne (Switzlerland)
- National Inst. for Materials Science (NIMS), Tsukuba (Japan)
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
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 π-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.
- Research Organization:
- National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- SC0001088
- OSTI ID:
- 1463266
- Journal Information:
- Science, Vol. 356, Issue 6340; ISSN 0036-8075
- Publisher:
- AAASCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Giant intrinsic photoresponse in pristine graphene
Anomalous periodicity of magnetic interference patterns in encapsulated graphene Josephson junctions