Amazing stuff! The holy grail of superconductors at room temperature and low pressure.
"... Conventional superconductors usually fail under magnetic fields of a certain strength. The new material continued to retain superconducting properties under a much higher magnetic field than the theoretical limit of a conventional superconductor. The team also measured how large an electrical current the new material can accommodate before it breaks superconductivity, applying electricity from one direction and then again from the opposite direction. The researchers found that one direction allowed notably higher current than the other. This is often referred to as the superconducting diode effect. In contrast, conventional superconductors would lose their zero-resistance property at equal current from either direction. ...
The UCLA-led team created a lattice with alternating layers. One layer made of tantalum disulfide, a conventional superconductor, was as thin as three atoms. The next was made of a “left-handed” or “right-handed” molecular layer of a different compound. The investigators tested tiny nanoscale devices made from their lattice to evaluate whether the material showed the properties of a chiral superconductor. ..."
From the abstract:
"Chiral superconductors, a unique class of unconventional superconductors in which the complex superconducting order parameter winds clockwise or anticlockwise in the momentum space, represent a topologically non-trivial system with intrinsic time-reversal symmetry breaking (TRSB) and direct implications for topological quantum computing. Intrinsic chiral superconductors are extremely rare, with only a few arguable examples, including UTe2, UPt3 and Sr2RuO4. It has been suggested that chiral superconductivity may exist in non-centrosymmetric superconductors, although such non-centrosymmetry is uncommon in typical solid-state superconductors. Alternatively, chiral molecules with neither mirror nor inversion symmetry have been widely investigated. We suggest that an incorporation of chiral molecules into conventional superconductor lattices could introduce non-centrosymmetry and help realize chiral superconductivity. Here we explore unconventional superconductivity in chiral molecule intercalated TaS2 hybrid superlattices. Our studies reveal an exceptionally large in-plane upper critical field Bc2,|| well beyond the Pauli paramagnetic limit, a robust π-phase shift in Little–Parks measurements and a field-free superconducting diode effect (SDE). These experimental signatures of unconventional superconductivity suggest that the intriguing interplay between crystalline atomic layers and the self-assembled chiral molecular layers may lead to exotic topological materials. Our study highlights that the hybrid superlattices could lay a versatile path to artificial quantum materials by combining a vast library of layered crystals of rich physical properties with the nearly infinite variations of molecules of designable structural motifs and functional groups."
Illustration of lattice with alternating layers in purple and yellow, and pink and gray
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