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تسجيل مستخدم جديدBand structure dependent electronic localization in macroscopic films of single-chirality single-wall carbon nanotubes
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Much understanding exists regarding chirality-dependent properties of single-wall carbon nanotubes (SWCNTs) on a single-tube level. However, macroscopic manifestations of chirality dependence have been limited, especially in electronic transport, despite the fact that such distinct behaviors are needed for any applications of SWCNT-based devices. In addition, developing reliable transport theory is challenging since a description of localization phenomena in an assembly of nanoobjects requires precise knowledge of disorder on multiple spatial scales, particularly if the ensemble is heterogeneous. Here, we report the observation of pronounced chirality-dependent electronic localization in temperature and magnetic field dependent conductivity measurements on single-chirality SWCNT films. The samples included semiconducting (6,5) and (10,3) films, chiral metallic (7,4) and (8,5) films, and armchair (6,6) films. Experimental data and theoretical calculations revealed variable-range-hopping dominated transport in all samples except the armchair SWCNT film. We obtained localization lengths that fall into three distinct categories depending on their band gaps. The clear deviation of the armchair films from the other films suggests their robustness toward defects and possible additional transport mechanisms. Our detailed analyses on electronic transport properties of single-chirality SWCNT films provide significant new insight into electronic transport in ensembles of nanoobjects, offering foundations for designing and deploying macroscopic SWCNT solid-state devices.
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