Disorder induced multifractal superconductivity in monolayer transition metal dichalcogenides

It is commonly believed that disorders have weak or detrimental effects on superconductivity. About one decade ago, it was proposed that disorder can enhance superconductivity by driving the electron wavefunctions to the so-called multifractal regime. However, no examples of multifractal superconductors have been identified. In this work, using a realistic model for monolayer NbSe₂, we calculated the superconducting pairing gap self-consistently and show that the pairing gap can be enhanced by several times at the intermediate disorder regime. Importantly, the enhancement of superconductivity can be traced to the strengthening of electron-electron correlation due to the multifractal wavefunctions. We suggest that monolayer NbSe₂ gives the first example of the long sought after multifractal superconductors.