Hysteretic Magnetotransport in SmB6 at Low Magnetic Fields

Utilizing Corbino disc structures, we have examined the magnetic field response of resistivity for the surface states of SmB6 on different crystalline surfaces at low temperatures. Our results reveal a hysteretic behavior whose magnitude depends on the magnetic field sweep rate and temperature. Although this feature becomes smaller when the field sweep is slower, a complete elimination or saturation is not observed in our slowest sweep-rate measurements, which is much slower than a typical magnetotransport trace. These observations cannot be explained by quantum interference corrections such as weak anti-localization. Instead, they are consistent with behaviors of glassy surface magnetic ordering, whose magnetic origin is most likely from samarium oxide (Sm2O3) forming on the surface during exposure to ambient conditions

Characterization of room temperature metal microbolometers near the metal-insulator transition regime for scanning thermal microscopy

Metal microbolometers, used in scanning thermal microscopy, were microfabricated from <20?nm titanium thin films on SiO2/Si3N4/SiO2 cantilevers. These thin films are near the metal-insulator transition regime such that as the film thickness decreases—the resistance increases and the current-voltage characteristics cross over from sublinear to superlinear. In addition, the temperature coefficient of resistance transitions from positive to negative before it plateaus at a negative value. Thin titanium films exhibit negative temperature coefficient of resistance as high as ?0.0067/K which is higher than that of bulk titanium films.Electrical Engineering, Mathematics and Computer Scienc