Next steps involve exploring how to control Majorana modes and how changes in thickness or external fields affect the superconducting and topological properties.

The discovery provides a practical, intrinsic material platform that does not require layered structures or exotic conditions to host Majorana particles, potentially advancing stable quantum device architectures.

The superconductivity observed in PtBi2 is topological with a six-fold electron-pairing symmetry tied to the material’s three-fold crystal symmetry, a first for superconductors.

PtBi2 shows surface-only superconductivity on its top and bottom surfaces while the interior remains metallic, creating a natural superconducting sandwich.

At low temperatures, surface electrons pair and move without resistance, but pairing occurs only along certain surface directions, revealing a six-fold rotational symmetry distinct from conventional superconductors.

The coexistence of gapless surface Majorana cones with a metallic bulk currently limits immediate quantum computing applications; potential routes include using ultrathin samples to suppress bulk modes or engineering time-reversal symmetry breaking to realize chiral Majorana edge modes or corner states.

The research team comprises scientists from IFW Dresden and ct.qmat, with collaborators at the Leibniz Institute for Solid State and Materials Research Dresden and the Würzburg-Dresden Cluster of Excellence ct.qmat, and the findings are published in Nature in 2025.

Edge-hinge Majorana modes are predicted to localize at sample hinges when time-reversal symmetry is preserved, and breaking TRS gaps these modes, offering experimental signatures of topological superconductivity.

The nodal gap function is modeled as i-wave, D(k) ∝ sin(6φ), implemented in a surface Wannier-based BdG framework to reproduce arc gaps and surface Majorana cones.

Temperature-dependent measurements show the nodal behavior persists up to a 10–15 kelvin range, with the gap opening away from the node and peaking near θ ≈ 90°, then diminishing as arcs merge with bulk states.

ARPES at multiple photon energies reveals highly resolved Fermi arcs on PtBi2 with a leading-edge gap that closes at the arc center, indicating nodes.

PtBi2’s edges host Majorana particles trapped along edges, which could be manipulated via fabricating step edges, thinning, or applying magnetic fields to move Majoranas between edges and corners, enabling qubit control.