Planar array of semiconducting nanotubes in external electric field: Collective screening and polarizability

TL;DR

This paper provides an analytical study of charge separation, polarizability, and field enhancement in a planar array of semiconducting nanotubes under an external electric field, revealing how these properties depend on nanotube parameters.

Contribution

It introduces an exact analytical method using conformal mapping to analyze charge distribution and polarizability in nanotube arrays under external electric fields.

Findings

Narrowing of the neutral charge strip with increasing electric field

Dependence of polarizability on the energy gap E_g

Enhanced electric field near nanotube tips

Abstract

We study theoretically the charge separation in a planar array of semiconducting nanotubes (NTs) of length, 2h, placed in external electric field, F, parallel to their axes. By employing the conformal mapping, we find analytically the exact distribution of the induced charge density for arbitrary ratio of the gap, E_g, and the voltage drop, eFh, across the NT. We use the result obtained to (i) trace the narrowing of the neutral strip at center of the NT with increasing F; (ii) analyze the polarizability of the array as a function of E_g; (iii) study the field enhancement near the tips.