22 May 2025
A team led by LMU physicist Dmitri Efetov has shown that two graphene layers twisted at an angle to each other behave like heavy-fermion metals. This opens up possibilities for the development of new applications.
If you twist two graphene layers at a certain angle to each other, you obtain a superconducting material, which is capable of a variety of further exotic quantum phases. Only discovered in 2018, this magic-angle twisted graphene is an ideal candidate for novel quantum devices. However, we still do not understand in detail how this unusual behavior comes about.
An international team led by LMU physicist Dmitri Efetov has made progress in this area: Using measurements of thermal conductivity, the researchers have demonstrated that the twisted graphene bilayers behave like so-called heavy-fermion metals. This class of crystalline materials has long been known and there are established theoretical models to describe their behavior. Now this knowledge can be applied to magic-angle twisted graphene, which could help scientists develop novel applications.
Rafael Luque Merino, Dmitri K. Efetov et. al., Interplay between light and heavy electron bands in magic-angle twisted bilayer graphene. In: Nature Physics, 2025.
Read the full LMU press release