Anomalous photoconductance band inC60single crystal

In the photoconductance spectrum of a ${\mathrm{C}}_{60}$ single crystal, a pronounced peak is found near 1.65 eV, corresponding to the weak absorption band. It is discriminated from the broad photoconductance band appearing above 1.8 eV, in its temperature and irradiation intensity dependences. The photoconductance exhibits a superlinear dependence in contrast to the sublinear one appearing above 1.8 eV. The electronic states related to the photoconductance and the effects of crystalline imperfections are discussed.