Light-induced metal-insulator transition in Lu2V2O7

Ferromagnetic Mott-Hubbard insulator Lu2V2O7 has been studied under continu ous Ar laser irradiation. One of the photon energies, i.e. E = 2.41 eV, cor responds to a transition from the lower Hubbard band of the V 3d orbital to the upper Hubbard band. Upon cooling, the activation-type electrical resis tivity shows an anomalous drop within the temperature range of 70-130 K. Be low the transition temperature, the resistivity shows no appreciable temper ature dependence. The temperature increase due to the laser heating is esti mated to be within the range of 15-35 K, which cannot be responsible for th e observed anomalous drop of the resistivity. The metal-insulator transitio n is discussed in connection with the ferromagnetism of the present compoun d. (C) 2000 Elsevier Science Ltd. All rights reserved.