Dephasing in InAs/GaAs quantum dots

The room-temperature dephasing in InAs/GaAs self-assembled quantum dots is measured using two independent methods: spectal-hole burning and four-wave mixing. Dephasing times weakly dependent on the excitation density are found, with a low density value of $290\pm 80\hspace{0.5em}\mathrm{fs}$ from spectal-hole burning and of $260\pm 20\hspace{0.5em}\mathrm{fs}$ from four-wave mixing.