Zeeshan Hafiz M, Butt Mehwish K, Iqbal Muhammad A, Wang Shuanhu, Ren Lixia, Jin Kexin
Shaanxi Key Laboratory of Condensed Matter Structures and Properties and MOE Key Laboratory of Materials Physics and Chemistry, School of Science, Northwestern Polytechnical University, Xi'an 710072, China.
ACS Appl Mater Interfaces. 2020 Mar 4;12(9):11197-11203. doi: 10.1021/acsami.9b22162. Epub 2020 Feb 19.
The photoinduced phase transition at complex oxides remains one of the very important issues because of the emergent physics and potential applications. In particular, the mechanism of charge transfer at interfaces under irradiation is challenging. Herein, the photoinduced properties of manganite-buffered LaAlO/SrTiO interfaces with different thicknesses of the buffer layer are systematically investigated. The giant photoresponse is observed, and its relative change in resistance is about 6.24 × 10% at = 20 K for the sample with a buffer layer thickness of 4.8 nm. Moreover, the transition temperature is enhanced by increasing the thickness of the buffer layer. More importantly, the dead layer effect at the interfaces has been suppressed by using light. All these results are attributed to the charge transfer because of the octahedral tilting at low temperatures and provide a new kind of oxide-based optical devices, such as ultraviolet detectors. This piece of work will pave the way toward two-dimensional electron gas-based optoelectronic devices.
由于其涌现出的物理特性和潜在应用，复杂氧化物中的光致相变仍然是非常重要的问题之一。特别是，辐照下界面处的电荷转移机制具有挑战性。在此，系统地研究了具有不同厚度缓冲层的锰酸盐缓冲的LaAlO/SrTiO界面的光致特性。观察到了巨大的光响应，对于缓冲层厚度为4.8 nm的样品，在T = 20 K时其电阻的相对变化约为6.24×10%。此外，通过增加缓冲层的厚度，转变温度得到提高。更重要的是，利用光抑制了界面处的死层效应。所有这些结果都归因于低温下八面体倾斜导致的电荷转移，并提供了一种新型的基于氧化物的光学器件，如紫外探测器。这项工作将为基于二维电子气的光电器件铺平道路。
