NUSNNI-Nanocore, National University of Singapore, 117542 Singapore.
Phys Rev Lett. 2011 Sep 30;107(14):146802. doi: 10.1103/PhysRevLett.107.146802. Epub 2011 Sep 28.
We report optical, electrical and magnetotransport properties of oxygen deficient SrTiO(3) (SrTiO(3-x)) thin films fabricated by pulsed laser deposition technique. The oxygen vacancies (O(vac)) in the thin film are expected to be uniform. By comparing its electrical properties to those of bulk SrTiO(3-x), it was found that O(vac) in bulk SrTiO(3-x) is far from uniform over the whole material. The metal-insulator transition (MIT) observed in the SrTiO(3-x) film was found to be induced by the carrier freeze-out effect. The low temperature frozen state can be reexcited by Joule heating, electric and intriguingly magnetic field.
我们报告了通过脉冲激光沉积技术制备的氧空位 SrTiO(3) (SrTiO(3-x)) 薄膜的光学、电学和磁输运性质。薄膜中的氧空位（O(vac)）预计是均匀的。通过将其电学性质与大块 SrTiO(3-x) 的电学性质进行比较，发现大块 SrTiO(3-x) 中的 O(vac) 在整个材料中极不均匀。在 SrTiO(3-x) 薄膜中观察到的金属-绝缘体转变（MIT）被发现是由载流子冻结效应引起的。低温冻结状态可以通过焦耳加热、电场和有趣的磁场重新激发。
