Spectroscopy of chemically- and gate-doped carbon nanotubes at the ensemble and single particle level

通过引入或去除电荷对半导体进行掺杂可用于控制其电子和光学结构。这为制造具有新特性的通用材料提供了许多机会，主要是因为任何半导体属性或现象，如导电性，能量传输和耗散，以及它们检测和发射光的能力都受到电荷载流子浓度的影响。例如，如果没有对半导体掺杂的基本理解，过去50年的微电子和纳米电子革命就不可能实现。同样，纳米级半导体的掺杂对未来技术的发展起着关键作用，但还没有得到很好的理解或成熟。特别是一维半导体掺杂的控制和光谱评估有时仍处于起步阶段。在拟议的研究项目中，我们将抓住纯半导体碳纳米管（s-SWNTs）样品制造的最新进展和新的光谱发展所带来的机会，发展更好的理解和更大的控制s-SWNTs的掺杂。拟议研究的主要目标是A）发展一个强大的方法，为s-SWNTs的掺杂，B）研究用于检测掺杂水平的不同光谱探针的灵敏度，C）更好地理解并可能消除掺杂的s-SWNT中的异质性，以及D）为定量预测掺杂对s-SWNT的性质的影响奠定基础，为了满足这些目标，我们将联合收割机与半导体s-SWNT样品的制备的最新进展与用于在系综和单粒子水平上研究掺杂的s-SWNT的新光谱工具相结合。特别是，我们将努力更好地了解化学和物理手段引起的掺杂的特点。化学掺杂将通过s-SWNTs与氧化还原剂的共价和非共价相互作用来实现，而物理掺杂将通过场诱导控制电化学potential. This研究的结果将有助于未来的定量分析和利用掺杂的s-SWNTs的基础研究以及潜在的应用。

Doping of semiconductors by the introduction or removal of charges can be used for controlling their electronic and optical structure. This offers many opportunities for the fabrication of versatile materials with new properties, essentially because any semiconductor attribute or phenomenon such as conductivity, energy transport and dissipation, as well as their ability to detect and emit light are affected by charge carrier concentrations. The micro- and nanoelectronic revolution of the past 50 years, for example, would not have been possible without a fundamental understanding of semiconductor doping. Similarly, the doping of nanoscale semiconductors plays a key role for the development of future technologies but is not nearly as well understood or matured. In particular the control and spectroscopic assessment of the doping of one-dimensional semiconductors is sometimes still in its infancy.Within the proposed research project we will seize the opportunity presented by recent advances with the fabrication of pure semiconducting carbon nanotube (s-SWNTs) samples and by new spectroscopic developments, for developing a better understanding and greater control of the doping of s-SWNTs.The key objectives of the proposed research aim at A) the development of a robust methodology for the doping of s-SWNTs by chemical and by physical processes, B) the investigation of the sensitivity of different spectroscopic probes for the detection of doping levels, C) a better understanding and possibly elimination of heterogeneity in doped s-SWNTs and D) laying the foundations for quantitative predictions of the effect of doping on the properties of s-SWNTs and other one-dimensional semiconductors.To meet these objectives we will combine recent advances with the preparation of semiconducting s-SWNT samples with new spectroscopic tools for the investigation of doped s-SWNTs at the ensemble and single particle level. In particular we will work toward a better understanding of the characteristics of doping, induced by chemical and by physical means. Chemical doping will here be achieved by covalent as well as non-covalent interactions of s-SWNTs with redoxactive agents while physical doping will be obtained by field-induced control of electrochemical potentials.The results of this research are expected to facilitate future quantitative analysis and utilization of doped s-SWNTs for fundamental research as well as for potential applications.