Construction of maximally localized Wannier functions

We present a general method for constructing maximally localized Wannier functions. It consists of three steps: (i) picking a localized trial wave function, (ii) performing a full band projection, and (iii) orthonormalizing with the Löwdin method. Our method is capable of producing maximally localized Wannier functions without further minimization, and it can be applied straightforwardly to random potentials without using supercells. The effectiveness of our method is demonstrated for both simple bands and composite bands.