{"id":305578,"date":"2025-11-21T17:53:37","date_gmt":"2025-11-21T17:53:37","guid":{"rendered":"https:\/\/www.newsbeep.com\/us\/305578\/"},"modified":"2025-11-21T17:53:37","modified_gmt":"2025-11-21T17:53:37","slug":"magic-angle-graphene-superconductivity-mystery-solved-by-scientists-using-tunnelling-spectroscopy","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us\/305578\/","title":{"rendered":"Magic-angle graphene superconductivity mystery solved by scientists using tunnelling spectroscopy"},"content":{"rendered":"

\"Three<\/p>\n

Scientists studying \u2018magic-angle\u2019 graphene have captured the clearest evidence yet of the electronic signature behind its superconductivity, cutting through years of speculation over what actually drives its exotic behaviour.<\/p>\n

\u2018When superconductivity was first discovered in magic-angle graphene, it was surprising,\u2019 says Jeong Min Park<\/a> at Princeton University. \u2018Graphene by itself was not a superconductor, yet simply twisting layers turned it into one.\u2019<\/p>\n

This is because when two or more graphene layers are twisted at a very specific angle<\/a> \u2013 the magic angle \u2013 electrons in the system slow down dramatically. \u2018When [this happens], they interact with each other much more strongly, and this gives rise to \u2026 new behaviours that don\u2019t exist in the individual layers,\u2019 says Park.<\/p>\n

\"Pairs<\/p>\n

A standout feature of magic-angle graphene is its extreme tunability. \u2018By applying small voltages nearby, a process called gating, you can turn the same device into a superconductor, an insulator or even a magnetic material,\u2019 says Park. \u2018One piece of magic-angle graphene behaves like thousands of different materials you can dial between.\u2019<\/p>\n

But this versatility comes at a cost: many electronic states lie close together, and their signals can overlap, making the desired electronic state hard to pinpoint. \u2018This complexity is a big reason why its superconductivity has remained such an intriguing mystery,\u2019 says Park.<\/p>\n

To solve it, Park and collaborators from Pablo Jarillo-Herrero<\/a>\u2019s group at the Massachusetts Institute of Technology used a combination of tunnelling spectroscopy and transport measurements to provide direct evidence linking a specific electronic gap to magic-angle graphene\u2019s superconducting state.<\/p>\n

\u2018Each experimental technique revealed a different piece of the puzzle,\u2019 she explains. \u2018Transport measurements tell us when electricity flows without resistance, which is how we know the material has become superconducting\u2026 Tunnelling spectroscopy, on the other hand, shows the energy structure of the electrons directly, and allow us to potentially see the superconducting gap.\u2019<\/p>\n

They revealed the coexistence of two distinct energy scales: the first is a small, low-energy gap that disappears at a critical temperature and magnetic field, identifying it as the true superconducting gap. The second is a larger \u2018pseudogap\u2019, which Park speculates may signal a precursor state where electron pairs have formed up, but superconductivity hasn\u2019t fully set in, or it reflects another electronic process that helps pave the way for superconductivity.<\/p>\n

\u2018This observation fundamentally challenges the simpler, single-gap model,\u2019 comments Antonio Castro Neto<\/a> at the National University of Singapore, who was not involved in the study. \u2018It provides the clearest evidence yet that superconductivity in this material is \u201cunconventional\u201d, likely involving electron pairs with a more complex structure.\u2019<\/p>\n

Beyond solving a long-standing mystery, the work lays the foundations for engineering quantum materials that could power future ultra-efficient quantum technologies. \u2018Magic-angle graphene hosts a whole zoo of quantum phases,\u2019 says Park. This makes it potentially useful for building quantum electronic circuits.<\/p>\n

\u2018However, we are far away from practical applications,\u2019 adds Castro Neto. \u2018Major hurdles remain, including the extremely low operating temperature, material stability issues and limited current capacity. The value of this discovery is primarily in fundamental science.\u2019<\/p>\n","protected":false},"excerpt":{"rendered":"Scientists studying \u2018magic-angle\u2019 graphene have captured the clearest evidence yet of the electronic signature behind its superconductivity, cutting…\n","protected":false},"author":2,"featured_media":305579,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[49],"tags":[199,79],"class_list":{"0":"post-305578","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-physics","9":"tag-science"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/305578","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/comments?post=305578"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/posts\/305578\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media\/305579"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/media?parent=305578"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/categories?post=305578"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us\/wp-json\/wp\/v2\/tags?post=305578"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}