Measurement of Transport Lifetime in a Cuprate Superconductor

We report measurements of the phase of the conductivity, $\phi_\sigma\equiv arg(\sigma)$, in the normal state of a $Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$ (BSCCO) thin film from 0.2-1.0 THz. From $\phi_\sigma$ we obtain the time delay of the current response, $\tau_\sigma\equiv\phi_\sigma/\omega$. 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.