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Modeling the electromagnetic response of carbon nanotube (CNT) reinforced composites is inherently a 3-D multiscale problem that is challenging to solve in real time for nondestructive evaluation (NDE) applications. This article presents a fast and accurate full-wave electromagnetic solver based on a multilayer dyadic Green’s function approach. In this approach, we account for the effects of the dielectric slab, where the CNTs are embedded, without explicitly discretizing its interfaces. Due to their large aspect ratios, the CNTs are modeled as arbitrary thin wires (ATWs), and the method-of-moment (MoM) formulation with distributed line impedance is used to solve for their coupled currents. The accuracy of the in-house solver is validated against the commercial MoM and the finite element method (FEM) solvers over a broad range of frequencies (from 1 GHz to 10 THz) and for a wide range of dielectric slab properties. Examples of 100 nm-long vertical and horizontal CNTs embedded in a 1 $\mu \text{m}$ -thick lossy dielectric substrate are presented. The in-house solver provides more than $50\times $ speed up while solving the vertical CNT and more than $570\times $ speed up while solving the horizontal CNT than a commercial MoM solver over the GHz-to-THz frequency range. [ABSTRACT FROM AUTHOR]

In this work, we study the use of asymmetric carbon nanotube (CNT) dimers for the contactless detection of foreign nano-particles. Asymmetric CNT dimers create a unique field distribution, through the electromagnetic coupling, which in turn generates two distinct resonances representing the bonding and anti-bonding modes. The presence of a foreign nano-particle (NP) in the vicinity of the CNT dimer perturbs the dimer’s field distribution and causes the bonding and antibonding resonances to shift by unequal amounts depending on the NP location. By studying the difference in the shift of the bonding and the anti-bonding resonances, we show that the NP relative location can be reconstructed. The computational experiments performed in this work show how asymmetric CNT dimers can be used for novel sensing applications. [ABSTRACT FROM AUTHOR]