Confinement in Graphene Nanostructures CONGRAN

石墨烯纳米结构中的约束 CONGRAN

• 批准号: 162680136
• 负责人: Professor Dr. Guido Burkard
• 金额: --
• 依托单位: Arbeitsgruppe Theoretische Festkörperphysik und Quanteninformation
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/162680136?language=en
• 关键词: Confinement; Graphene; Nanostructures; CONGRAN

Tunable graphene-based quantum dots offer unique advantages in comparison to conventional quantum dots made from semiconductor heterostructures, namely longer spin coherence times, novel spin effects, and the potential for a size reduction leading to operation of quantum dots at higher temperatures. However, transferring the conventional top gate technology to define tunable graphene-based quantum dots is nontrivial due to Klein tunneling. The project aims for the implementation and investigation of the three approaches for tunable confinement in graphene which are presently foreseen, namely combining lateral confinement with top gates, biased bilayer systems and magnetic confinement. Based on these results, graphene-based quantum dots will be tailored which potentially rely on all three confinement schemes and are optimized for the investigation of spin effects and operation at elevated temperatures. At the beginning of the project, each experimental partner will implement one confinement scheme, while the theory partners work on development of relevant models for the graphene based quantum dots, namely energy spectra, effects of disorder and interactions, and spin effects. These results will form the basis for the subsequent investigations of spin relaxation and pin decoherence, spin blockade and gdots at elevated temperatures.

与由半导体异质结构制成的常规量子点相比，可调谐石墨烯基量子点提供了独特的优势，即更长的自旋相干时间、新颖的自旋效应以及导致量子点在更高温度下操作的尺寸减小的潜力。然而，由于Klein隧穿，转移传统的顶栅技术以定义可调谐的石墨烯基量子点是不平凡的。该项目旨在实施和研究目前可预见的石墨烯可调约束的三种方法，即将横向约束与顶栅相结合，偏置双层系统和磁约束。基于这些结果，石墨烯基量子点将被定制，其可能依赖于所有三种限制方案，并针对自旋效应的研究和高温下的操作进行优化。在项目开始时，每个实验合作伙伴将实施一个限制方案，而理论合作伙伴则致力于开发基于石墨烯的量子点的相关模型，即能谱，无序和相互作用的影响以及自旋效应。这些结果将为后续的自旋弛豫和钉退相干，自旋封锁和gdots在高温下的研究奠定基础。