Superconducting Dome in a Gate-Tuned Band Insulator

What Do You Know? A Dome

The superconducting dome—the appearance of a maximum in the transition temperature as a function of a tuning parameter—has been observed in compounds such as cuprates, pnictides, and heavy fermion materials and is thought of as a signature of unconventional superconductivity. Ye et al. (p. 1193 ) used a liquid gating technique combined with back gating to finely tune the carrier density in the band insulator MoS ₂ , which allowed them to observe the formation of a dome. The unexpected finding awaits theoretical explanation but may suggest that the appearance of an optimal carrier density may be a more common occurrence than was previously thought.