Instability toward biexciton crystallization in one-dimensional electron–hole systems

One-dimensional (1D) electron–hole (e–h) systems in a high-density regime is investigated by means of bozonization techniques. It turned out that the systems are insulating even at the high-density limit and that the exciton Mott transition (insulator-to-metal transition) never occurs at absolute zero temperature. The insulating ground state exhibits a strong instability towards the crystallization of biexciton.