Ferromagnetic GaN based structures for room temperature spintronics: spin dynamics and spin interactions

用于室温自旋电子学的铁磁 GaN 基结构：自旋动力学和自旋相互作用

• 批准号: 40976387
• 负责人: Professor Dr. Daniel Hägele
• 金额: --
• 依托单位: Institut für Experimentalphysik VI: AG Spektroskopie der kondensierten Materie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/40976387?language=en
• 关键词: Ferromagnetic; GaN; based; structures; room

The observation of ferromagnetism of GaN:Gd and even GaN:Cu in SQUID measurements is still not well understood. We will perform sensitive static measurements of the magnetooptical Kerreffect to check if this (phantom) ferromagnetism has an influence on the conduction band and if it may be useful for applications in spin aligners. We will continue our time-resolved measurements on spin relaxation in wurtzite GaN based materials to explore heterostructures for improved spin lifetimes. These studies will be extended to the metastable cubic phase of GaN, where we will perform the first measurements on cubic GaN quantum wells and superlattices motivated by our recent findings of ns-spinlifetimes in bulk c-GaN at room temperature. Our preliminary results indicate open questions in cubic GaN like a weak temperature dependence or strong spatial variations of the spin lifetime. We plan spatial correlation of µ-photoluminescence data with spin lifetime data and time-resolved photoluminescence measurements to clarify e.g. the influence of the ever present hexagonal inclusions in cubic structures.

在SQUID测量中对GaN：Gd甚至GaN：Cu的铁磁性的观察仍然没有得到很好的理解。我们将执行敏感的磁光Kerreffect的静态测量，以检查这种（幻影）铁磁性是否对导带有影响，如果它可能是有用的自旋对准器中的应用。我们将继续对纤锌矿GaN基材料的自旋弛豫进行时间分辨测量，以探索改善自旋寿命的异质结构。这些研究将扩展到GaN的亚稳立方相，在那里我们将执行立方GaN量子威尔斯阱和超晶格的首次测量，我们最近的研究结果，在体c-GaN在室温下的ns-自旋寿命的动机。我们的初步结果表明，在立方GaN像一个弱的温度依赖性或强的空间变化的自旋寿命的开放性问题。我们计划将µ-光致发光数据与自旋寿命数据和时间分辨光致发光测量进行空间相关，以澄清例如立方结构中一直存在的六方夹杂物的影响。