Jesse Balgley, a graduate student in Henriksen's laboratory at Washington University, is second author of the study. Li Yang, professor of physics, and his graduate student Xiaobo Lu, also both at Washington University, helped with computational work and calculations, and are also co-authors.
Physicists who study condensed matter are intrigued by alpha-RuCl3 because they would like to exploit certain of its antiferromagnetic properties for quantum spin liquids.
In this new study, the scientists report that alpha-RuCl3 is able to transfer charge to several different types of materials -- not just graphene, Henriksen's personal favorite.
They also found that they only needed to place a single layer of alpha-RuCl3 on top of their devices to create and transfer charge. The process still works, even if the scientists slip a thin sheet of an electrically insulating material between the RuCl3 and the graphene.
"We can control how much charge flows in by varying the thickness of the insulator," Henriksen said. "Also, we are able to physically and spatially separate the source of charge from where it goes -- this is called modulation doping."
Adding charge to a quantum spin liquid is one mechanism thought to underlie the physics of high-temperature superconductivity.
"Anytime you do this, it could get exciting," Henriksen said. "And usually you have to add atoms to bulk materials, which causes lots of disorder. But here, the charge flows right in, no need to change the chemical structure, so it's a 'clean' way to add charge."
Read more in Nano Letters: Modulation Doping via a Two-Dimensional Atomic Crystalline Acceptor