Advanced Photonics Center, Southeast University, Nanjing, 210096, People's Republic of China.
Nanotechnology. 2017 Jan 20;28(3):035601. doi: 10.1088/1361-6528/28/3/035601. Epub 2016 Dec 8.
In this work, highly luminescent quaternary CuNiInS nanocrystals (NCs) are put forward as a good prototype for investigating defect-induced room temperature ferromagnetism. A ferromagnetic Ni cation can preserve the strong luminescence of NCs without introducing intermediate energy levels in the center of the forbidden band. The strong luminescence of NCs is used as an indicator for monitoring the concentration of vacancy defects inside them, facilitating the investigation of the origin of room temperature ferromagnetism in CuNiInS NCs. Our results reveal that the patching of Cu vacancies [Formula: see text] with Ni will result in bound magnetic polarons composed of both [Formula: see text] and a substitution of Cu by Ni [Formula: see text] giving rise to the room temperature ferromagnetism of CuNiInS NCs. Either the ferromagnetic Ni or the non-ferromagnetic Cu cation can tune the magnetism of CuNiInS NCs because of the change of bound magnetic polaron concentration at the altered concentration ratio of [Formula: see text] and [Formula: see text].
在这项工作中，我们提出了具有高光致发光性能的四元 CuNiInS 纳米晶体（NCs），作为研究缺陷诱导室温铁磁性的良好模型。具有铁磁性的 Ni 阳离子可以在禁带中心不引入中间能级的情况下保持 NCs 的强发光性。NCs 的强发光性被用作监测它们内部空位缺陷浓度的指示剂，这有助于研究 CuNiInS NCs 中室温铁磁性的起源。我们的结果表明，用 Ni 修补 Cu 空位[Formula: see text]将导致由[Formula: see text]和 Cu 被 Ni 取代[Formula: see text]组成的束缚磁极化子，从而导致 CuNiInS NCs 的室温铁磁性。由于[Formula: see text]和[Formula: see text]的浓度比值发生变化，导致束缚磁极化子浓度发生变化，因此无论是铁磁性的 Ni 阳离子还是非铁磁性的 Cu 阳离子都可以调节 CuNiInS NCs 的磁性。
