Stress-Induced In Situ Modification of Transition Temperature in VO Films Capped by Chalcogenide.

We attempted to modify the monoclinic-rutile structural phase transition temperature () of a VO thin film in situ through stress caused by amorphous-crystalline phase change of a chalcogenide layer on it. VO films on C- or R-plane AlO substrates were capped by GeSbTe (GST) films by means of rf magnetron sputtering. of the VO layer was evaluated through temperature-controlled measurements of optical reflection intensity and electrical resistance.

Overcoming the thermal regime for the electric-field driven Mott transition in vanadium sesquioxide.

The complex interplay among electronic, magnetic and lattice degrees of freedom in Mott-Hubbard materials leads to different types of insulator-to-metal transitions (IMT) which can be triggered by temperature, pressure, light irradiation and electric field. However, several questions remain open concerning the quantum or thermal nature of electric field-driven transition process. Here, using intense terahertz pulses, we reveal the emergence of an instantaneous purely-electronic IMT in the Mott-Hubbard vanadium sequioxide (VO) prototype material.

Pump-probe STM light emission spectroscopy for detection of photo-induced semiconductor-metal phase transition of VO.

We attempted to observe pump-probe scanning tunneling microscopy (STM)-light emission (LE) from a VO thin film grown on a rutile TiO(0 0 1) substrate, with an Ag tip fixed over a semiconducting domain. Laser pulses from a Ti:sapphire laser (wavelength 920 nm; pulse width less than 1.5 ps) irradiated the tip-sample gap as pump and probe light sources.

Selective scanning tunneling microscope light emission from rutile phase of VO2.

We observed scanning tunneling microscope light emission (STM-LE) induced by a tunneling current at the gap between an Ag tip and a VO2 thin film, in parallel to scanning tunneling spectroscopy (STS) profiles. The 34 nm thick VO2 film grown on a rutile TiO2 (0 0 1) substrate consisted of both rutile (R)- and monoclinic (M)-structure phases of a few 10 nm-sized domains at room temperature. We found that STM-LE with a certain photon energy of 2.

A case of Vogt-Koyanagi-Harada disease that developed relapsing polychondritis.

We report the case of a 56-year-old Japanese man with Vogt-Koyanagi-Harada disease in whom pain and diffuse swelling of the left auricle and bilateral episcleritis developed 3 years after diagnosis. Biopsy of the left ear showed acute chondritis, leading to another diagnosis of relapsing polychondritis. Additionally, he was found to carry human leukocyte antigen DR4, which has been reported to be associated with these inflammatory conditions.

Magnetism in V-doped ZnO thin films.

Ferromagnetism at room temperature, along with a spin-glass-like behaviour at low temperatures, has been observed in laser ablated V-doped ZnO thin films. It is found that V atoms were well substituted for Zn atoms and resulted in a very uniform distribution among the ZnO matrices.