A topological insulator (TI) is an exotic material that has a bulk insulating gap and metallic surface states with unique spin-momentum locking characteristics. Despite its various important applications, large scale integration of TI into MOSFET technologies and its coherent transport study are still rarely explored. Here, we report the growth of high quality Bi2Se3 thin film on amorphous SiO2/Si substrate using MBE. By controlling the thickness of the film at ∼7 nm and capping the as grown film in situ with a 2 nm-thick Se layer, largest electrostatic field effect is obtained and the resistance is changed by almost 300%. More importantly, pronounced gate-tunable weak antilocalization (WAL) is observed, which refers to modulation of α from ∼−0.55 to ∼−0.2 by applying a back gate voltage. The analysis herein suggests that the significant gate-tunable WAL is attributable to the transition from weak disorder into intermediate disorder regime when the Fermi level is shifted downward by increasing the negative back gate voltage. Our findings may pave the ways towards the development of TI-based MOSFET and are promising for the applications of electric-field controlled spintronic and magnetic device.

Our results showed that administration of DHEA during allergic sensitization could attenuate the subsequent allergic responses elicited by challenge, and that the suppressive effect of DHEA was associated with a down-regulation of TH2 response.

In this investigation, Mg-doped ZnO nanorods were synthesized successfully on a glass substrate at 80°C by hydrothermal method. The average length and diameter of the Mg-ZnO nanorods were 609 nm and approximately 50 nm, respectively. The X-ray diffraction spectrum showed the Mg-ZnO nanorods had a wurtzite hexagonal phase. The Mg-doped ZnO nanorods are found to be single crystals grown along the c-axis. The photosensors showed good stability properties in ultraviolet (UV) illumination. The resulting Mg-doped ZnO nanorods have excellent potential for application in a UV photodetector (PD) because of the Mg-doped ZnO nanorods UV PD has a high UV-to-visible ratio, fast rise/fall time. Furthermore, the dynamic response of the Mg-doped ZnO nanorods PD with Au electrodes was stable and reproducible with an on/off current contrast ratio of approximately 4 × 10 3 . The ultraviolet-to-visible rejection ratio of the sample is approximately 400 when biased at 1 V, and the fabricated UV PD is visible-blind with a sharp cutoff at 350 nm. The low-frequency noise spectra obtained from the UV PD were caused purely by the 1/f noise. The noise-equivalent power and normalized detectivity (D * ) of the Mg-ZnO nanorod PD were 0.335 × 10 −9 W and 1.49 × 10 8 cm · Hz 0.5 · W −1 , respectively.Index Terms-Mg-ZnO, hydrothermal method, noise.

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