April 19, 2026 by Ellen Neff, Columbia University Quantum Initiative
Collected at: https://phys.org/news/2026-04-range-magic-angles-superconductivity-2d.html
Last year, tungsten diselenide (WSe2) had its magic moment. Two independent research groups discovered “magic angles” at which two atom-thin layers of the unique semiconductor, when twisted relative to one another into what’s known as a moire pattern, can superconduct electricity. Cory Dean and his colleagues at Columbia documented superconductivity at a 5° twist angle; upstate at Cornell, Jie Shan and Kin Fai Mak’s team saw it at around 3.5°. Until then, graphene was the only other moire material capable of the feat.
Writing again in Nature on April 1, Dean and his colleagues fill in what happens between their observed magic angle and Cornell’s. Though the initial results struck researchers as two potentially distinct types of superconductivity, they are in fact smoothly connected. “Graphene has a magic angle of 1.1°. WSe2 has a magic continuum,” said Columbia physics graduate student Yinjie Guo, lead author of both Columbia Nature papers.
That wide continuum of superconducting twist angles makes WSe2 a more robust platform to explore the phenomenon than graphene, which cannot deviate by more than a tenth of a degree from its magic angle. “That’s a very specific condition you have to get to, and it’s been a real bottleneck,” noted Dean. “Working with WSe2 is extremely reproducible, which makes it much more possible to build new theories about superconductivity.”
Broadly defined, superconductivity is a state in which electrons move with zero resistance. In normal conductors, electrons bounce around against each other and the material they are moving through, and eventually, many are lost as heat. Electrons in superconductors flow without experiencing any such friction, making them perfect conductors of electricity. To achieve a superconducting state, the electrons must pair up, or in physics parlance, become correlated, with different theories about how that pairing ultimately occurs.
In the current work, Dean’s team prepared several WSe2 samples with twist angles ranging from 3.65° to 5° and measured how the material responded to twist angle and electrical field. At larger angles, the electron pairing resembles that of conventional superconductors, but as the angle shrinks, the behavior increasingly appears to look like that of a class of high-temperature superconducting materials called the cuprates. Discovered in the 1980s, cuprates superconduct at liquid-nitrogen rather than liquid-helium temperatures, which is easier and cheaper to reach.
“With this system, we can move from a regime that resembles conventional superconductors to one that is more strongly correlated by modifying twist angle and electric field,” said Dean. “We can smoothly turn those knobs.”
The team’s tunable WSe2 platform is the culmination of collaborative efforts across Columbia and with colleagues at the Flatiron Institute and Max Planck Institute for Structural Dynamics. These include advances in materials engineering to improve the material’s quality; device engineering to achieve the necessary electrical contacts for the experiments; and theoretical discussions that reproduced pivotal aspects of the experimental result and yielded microscopic insight into the angle evolution.
Beyond the ability to explore the origins of superconductivity, Dean also notes a unique feature of WSe2: it is a semiconductor. A semiconductor that also superconducts is a rare find, with implications for devices as researchers consider the energy demands of electronics and how to engineer quantum states in emerging quantum computers. If paired with other materials that host unique forms of magnetism or topological states, there are even more possibilities to dream of.
“The specific phase diagram we observe in twisted WSe2 results from a delicate balance between competing effects,” said Dean. “But WSe2 is just one of many similar materials available, called the transition metal dichalcogenides or TMDs. Replacing WSe2 could significantly alter this phase diagram, suppress or enhance superconductivity, or even yield entirely new behaviors.”
Publication details
Yinjie Guo et al, Angle evolution of the superconducting phase diagram in twisted bilayer WSe2, Nature (2026). DOI: 10.1038/s41586-026-10357-2
Journal information: Nature
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