Non-Abelian braiding statistics via Aharonov–Bohm interferometry

One of the most striking consequences of the non-Abelian braiding statistics in the ν=5/2 quantum Hall state has been the so-called even–odd effect theoretically predicted over a decade ago. While signatures consistent with the theoretical prediction have been seen in quantum Hall Fabry–Pérot interferometers, the key ingredient – controlling the number of quaiparticles inside the interferometer – remains a challenging experimental problem. Fortunately, signatures of the non-Abelian statistics can emerge in a simpler setting, namely in Aharonov–Bohm-type experiments where interference patterns are produced solely by changing the magnetic field. This nucleates new quasiparticles inside the interferometer, and if those include non-Abelian particles, the Aharonov–Bohm oscillations are expected to have distinct spectral features that would be absent otherwise. This talk will focus on the theoretical predictions and their comparison with the recent observations [1], arguing that the preponderance of experimental evidence unmistakably points towards the non-Abelian nature of ν=5/2 and 7/2 quantum Hall states and provides strong evidence of non-Ableian braiding.

1. R. L. Willett, K. Shtengel, C. Nayak, L. N. Pfeiffer, Y. J. Chung, M. L. Peabody, K. W. Baldwin, K. W. West, arXiv:1905.10248