The EFM profiles for semiconducting and metallic SWNTs. In column (a), the effect of the EFM tip crossing a semiconductor (blue) and a metallic (red) SWNTs on is shown. The lineshapes are different due to the differences in dielectric response. In column (b) the effect of the EFM tip retracting from the substrate on is shown. Here the effect is the same for both semiconductors and metals. In column (c) the two effects are combined. The equations in  were used to build these plots .
Article of the Year Award: Outstanding research contributions of 2020, as selected by our Chief Editors. Read the winning articles.