Excitonic lasing in semiconductor quantum wires

Direct experimental evidence for excitonic lasing is obtained in optically pumped V-groove quantum wire structures. We demonstrate that laser emission at a temperature of 10 K arises from a population inversion of localized excitons within the inhomogeneously broadened luminescence line. At the lasing threshold, we estimate a maximum exciton density of about $1.8\times {10}^5\hspace{0.5em}{\mathrm{cm}}^{\mathrm{-}1}.$