Unconventional Superconductivity in Graphene Bilayers

March 26, 2018
 image of one layer and a two-layer stack of graphene

Image courtesy of the researchers

Much of the appeal of the two-dimensional materials zoo—which includes graphene, hexagonal boron nitride, molybdenum disulfide, and many others—lies in the multitude of ways the atomically thin sheets can be stacked and combined to create new structures with novel properties. Compounding the number of potential arrangements is the possibility of tuning the twist angle between successive layers. Now [scientists from MIT, Harvard (grad student Shiang Fang and Prof. Efthimios Kaxiras), and National Institute for Materials Science, Tsukuba, Japan, Pablo Jarillo-Herrero and colleagues have shown that the twist angle between two sheets of graphene can be exploited to dramatic effect: At a so-called magic angle of approximately 1.1°, the two-layer stack becomes a superconductor.

Continue reading "Unconventional superconductivity in graphene bilayers" by Johanna L. Miller, Physics Today, Mar 22, 2018.

Also read Eugene J. Mele, "Novel electronic states seen in graphene,"Nature, Mar 5, 2018, and the original article: Yuan Cao,Valla Fatemi, Shiang Fang, Kenji Watanabe, Takashi Taniguchi, Efthimios Kaxiras & Pablo Jarillo-Herrero, "Unconventional superconductivity in magic-angle graphene superlattices," Nature (unedited manuscript accepted for publication) doi:10.1038/nature26160.