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

通过引入或去除电荷来掺杂半导体可用于控制其电子和光学结构。这为制造具有新性能的多功能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、能量输运和耗散，以及它们的探测和发光能力都受到载流子浓度的影响。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是不可能实现的。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，但还没有被充分理解或成熟。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以及新的光谱发展所带来的机会，以更好地理解和更好地控制s-SWNTs的掺杂。提出的研究的主要目标是：A)开发一种强有力的方法，通过化学和物理方法掺杂s- swcnts； B)研究不同光谱探针检测掺杂水平的灵敏度；C)更好地理解并可能消除掺杂s-SWNTs的非均质性；D)为定量预测掺杂对s-SWNTs和其他一维半导体性质的影响奠定基础。为了实现这些目标，我们将结合半导体s-SWNT样品的制备和新的光谱工具，在系综和单粒子水平上研究掺杂s-SWNT。特别是，我们将努力更好地了解兴奋剂的特点，通过化学和物理手段诱导。化学掺杂将通过s- swcnts与氧化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电位来实现。这项研究的结果有望促进未来的定量分析和利用掺杂s- swcnts进行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.