6 research outputs found
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