Funding information National Key Basic Research Development Program of China, Grant/ Award Number: 2012CB722705; National Natural Science Foundation of China, Grant/Award Number: 10974105; Program for Foreign Cultural and Educational Experts, Grant/Award Number: GDW20143500163, GDW20163500110; Top-notch Innovative Talent Program of Qingdao City, Grant/Award Number: 13-CX-8 In this paper the effect of thickness on angular-dependent magnetoresistance (MR) of La2/3Sr1/3MnO3 (LSMO) thin films grown on SrTiO3 is systematically investigated. In films thinner than 8 nm, we observe an anomalous weak peak in the MR curves when the magnetic field is parallel to the film surface. In films thicker than 10 nm, however, the weak peak disappears and a novel MR valley appears when the magnetic field is perpendicular to the film surface. The weak peak is thought to be induced by the formation of two-dimensional electron gas (2DEG) at the interface, which is confirmed by density functional theory calculations. The disappearance of the peak and appearance of the valley in the films thicker than 10 nm is associated with the formation of misfit dislocations near the interface between film and substrate, which are clearly visible in high-resolution transmission electron microscopy images. Our work could shed significant light on the influence of film thickness on 2DEG formation.

中文翻译：

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在 SrTiO3 上生长的 La2/3 Sr1/3 MnO3 薄膜的厚度引起的异常角度相关磁阻

基金信息 国家重点基础研究发展计划，资助/奖励号：2012CB722705；国家自然科学基金，资助/奖励号：10974105；外国文教专家计划，资助/奖励编号：GDW20143500163、GDW20163500110；青岛市拔尖创新人才计划，资助/奖励编号：13-CX-8 在本文中，厚度对 SrTiO3 上生长的 La2/3Sr1/3MnO3 (LSMO) 薄膜的角相关磁阻 (MR) 的影响为系统地调查。在薄于 8 nm 的薄膜中，当磁场平行于薄膜表面时，我们观察到 MR 曲线中的异常弱峰。然而，在厚度超过 10 nm 的薄膜中，当磁场垂直于薄膜表面时，弱峰消失并出现新的 MR 谷。弱峰被认为是由界面处二维电子气（2DEG）的形成引起的，密度泛函理论计算证实了这一点。厚度超过 10 nm 的薄膜中峰的消失和谷的出现与薄膜和基板之间界面附近错配位错的形成有关，这在高分辨率透射电子显微镜图像中清晰可见。我们的工作可以揭示薄膜厚度对 2DEG 形成的影响。厚度超过 10 nm 的薄膜中峰的消失和谷的出现与薄膜和基板之间界面附近错配位错的形成有关，这在高分辨率透射电子显微镜图像中清晰可见。我们的工作可以揭示薄膜厚度对 2DEG 形成的影响。厚度超过 10 nm 的薄膜中峰的消失和谷的出现与薄膜和基板之间界面附近错配位错的形成有关，这在高分辨率透射电子显微镜图像中清晰可见。我们的工作可以揭示薄膜厚度对 2DEG 形成的影响。