Normal State ac Hall Effect in YB${\mathrm{a}}_2$C${\mathrm{u}}_3$${\mathrm{O}}_7$ Thin Films

We have measured the magnetotransmission of thin film samples of YB${\mathrm{a}}_2$C${\mathrm{u}}_3$ ${\mathrm{O}}_7$ in the normal state using circularly polarized light at frequencies from 15 to $180{\mathrm{cm}}^{-1\mathrm{}}$. The magneto-optical signal is consistent with the ac Hall effect of holes with a reduced scattering rate and an enhanced mass compared to the zero-field transport parameters. This result agrees with a simple high-frequency extension of models which have been developed to explain the anomalous dc Hall effect in the normal state of high- $T_c$ superconductors.