• Superfluid stiffness quantifies how easily electron pairs flow without resistance. • MIT and Harvard scientists directly measured this property in magic‑angle graphene. • Magic‑angle graphene consists of two graphene sheets twisted at a precise angle, enabling superconductivity. • The measurement clarifies the underlying mechanism of superconductivity in this novel material. • Results indicate quantum geometry largely governs the superconducting behavior. • First direct stiffness measurement opens pathways for quantum‑computing device design.

Article Summaries:

  • MIT and Harvard physicists have, for the first time, directly measured the superfluid stiffness of magic‑angle twisted bilayer graphene (MATBG), a two‑dimensional material that becomes superconducting when two graphene sheets are twisted at a precise “magic” angle. The measurement, reported in Nature, shows that the superconductivity in MATBG is largely governed by quantum geometry-the shape of its electronic states-rather than conventional mechanisms. The team developed a new experimental technique that can be applied to other 2D superconductors, opening a pathway to probe the fundamental physics of these materials and their potential use in quantum‑computing devices.

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