Measurement of Transport Lifetime in a Cuprate Superconductor

We report measurements of the phase of the conductivity, $\phi_\sigma\equiv arg(\sigma)$,inthenormalstateofa$Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$(BSCCO)thinfilmfrom0.2-1.0THz\mathrm{.}From$\phi_\sigma$ we obtain the time delay of the current response, ${\tau }_{\sigma }\equiv {\varphi }_{\sigma }\mathrm{/}\omega$. After discovering a systematic error in the data analysis, the extracted ${\tau }_{\sigma }$ has changed from that reported earlier. The revised data is shown in the sole figure below. Analysis and discussion of these data will follow.