Quenched high-temperature-phase MnBi film was successfully obtained by
quenching the low-temperature phase MnBi film in air. The high-temper
ature-phase has been found to appear below 300-degrees-C, which is dif
ferent from a previously reported result. Its Kerr rotation and Kerr e
llipticity spectra have been measured at room temperature, and are ver
y different from that of the low-temperature-phase MnBi film in both m
agnitude and spectral structure.