Sliding Wigner crystals in bilayer graphene at zero and finite magnetic fields

Anna M. Seiler, Martin Statz, Christian Eckel, Isabell Weimer, Jonas Pöhls, Kenji Watanabe, Takashi Taniguchi, Fan Zhang, R. Thomas Weitz

Published 2024-08-29Version 1

AB-stacked bilayer graphene has emerged as a fascinating yet simple platform for exploring macroscopic quantum phenomena of correlated electrons. Unexpectedly, an insulating phase has recently been observed when a large electric displacement field is applied and the charge carrier density is tuned to the vicinity of an ultra-low-density van Hove singularity. This phase exhibits features consistent with Wigner crystallization, including a characteristic temperature dependence and non-linear current bias behavior. However, more direct evidence for the emergence of an electron crystal in AB-stacked bilayer graphene at zero magnetic field remains elusive. Here we explore the low-frequency noise generated by the depinning and sliding of the Wigner crystal lattice. The current bias and frequency dependence of these noise spectra align well with findings from previous experimental and theoretical studies on the quantum electron solids. Our results offer a compelling transport signature of Wigner crystallization in AB-stacked bilayer graphene at zero and finite magnetic fields, paving the way for further substantiating an anomalous Hall crystal in its original form.