A second study shows that FeTe's superconductivity can be engineered through layered structures and moiré effects at interfaces by placing a top layer with a different lattice to create a moiré superlattice.

The work redefines the phase diagram of iron-containing compounds and suggests that removing disorder can reveal hidden superconducting states in other correlated materials.

Exposing FeTe films to tellurium vapor to remove excess iron yields a near-pure composition and induces superconductivity with a critical temperature around 13.5 Kelvin.

Both studies were led by Cui-Zu Chang of Penn State and published in Nature in March 2026, supported by multiple funding sources including the U.S. Department of Energy and the National Science Foundation.

These findings underscore the crucial role of lattice structure and interface engineering in controlling superconductivity and highlight moiré engineering as a pathway for designing next-generation quantum materials.

A new study shows iron telluride (FeTe), once thought magnetic and non-superconducting, becomes superconducting when excess iron atoms are removed from its lattice.

Molecular beam epitaxy produced ultra-clean FeTe thin films, revealing that embedded excess iron disrupts the Fe-Te ratio and suppresses superconductivity.

The moiré pattern at the interface modulates superconductivity, creating a droplet-like, repeating superconducting pattern that follows the moiré lattice and is tunable by the top-layer material.