标题: | 利用时间解析磁光柯尔效应光谱研究受应力之La0.7Sr0.3MnO3薄膜磁化动力学 Magnetization Dynamics in Strained La0.7Sr0.3MnO3 Thin Film Probed by Time-Resolved Magneto-Optical Kerr Effect Spectroscopy |
作者: | 廖淑雯 Liao, Shu-Wen 吴光雄 Wu, Kaung-Hsiung 电子物理系所 |
关键字: | 磁光效应;应变效应;庞磁阻;Magneto-Optical Kerr Effect;Strain Effect;CMR |
公开日期: | 2010 |
摘要: | 钙钛矿锰锰氧化物La0.7Sr0.3MnO3在居礼温度Tc = 380 K以下具有铁磁金属态。而在本文的实验中,利用雷射蒸镀系统分别在SrTiO3(100)、 LaAlO3(100)和NdGdO3(110)成长出受不同应变之La0.7Sr0.3MnO3薄膜。应变形态的不同可影响La0.7Sr0.3MnO3薄膜的磁各向异性,进而利用时间解析柯尔效应光谱来探测其光致磁化动力学,藉由分析柯尔旋转角的变化,得到因薄膜不同的应变效应导致进动周期的改变与光致去磁化的时间,本文将对于所观察到因应变效应而影响磁动力行为可能的机制进行讨论。 Perovskite manganite La0.7Sr0.3MnO3 show the ferromagnetic metal phase below Tc = 380 K. In this work, the (001)-oriented La0.7Sr0.3MnO3 with various nominal strain state were deposited on SrTiO3(100), LaAlO3(100) and NdGdO3(110) substrates by pulsed laser deposition. The magnetic anisotropy may be change dependent on the type of strain. The photoinduced dynamics of magnetization is probed by Time-Resolved Magneto-Optical Kerr Effect Spectroscopy. Analyses based on the measured Kerr angle-change(ΔθK) curves revealed that while the period of the precession and photoinduced demagnetization time changes with the variation of the thin film strain effect. The possible mechanism for the observed strain effect on the dynamics of magnetization is discussed. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT079821546 http://hdl.handle.net/11536/47477 |
显示于类别: | Thesis |