Multiple Cotunneling in Large Quantum Dot Arrays

TL;DR

This paper studies how inelastic cotunneling affects electronic transport in large quantum dot arrays, revealing Efros-Shklovskii hopping behavior and linking hopping distance to current-voltage characteristics.

Contribution

It provides new insights into cotunneling effects in quantum dot arrays, connecting hopping transport with measurable electrical properties.

Findings

Zero-bias conductance shows Efros-Shklovskii-type hopping.

Hopping distance relates to the power law in I-V characteristics.

Cotunneling influences transport in mesoscopic granular conductors.

Abstract

We investigate the effects of inelastic cotunneling on the electronic transport properties of gold nanoparticle multilayers and thick films at low applied bias, inside the Coulomb blockade regime. We find that the zero-bias conductance, $g_0(T)$, in all systems exhibits Efros-Shklovskii-type variable range hopping transport. The resulting typical hopping distance, corresponding to the number of tunnel junctions participating in cotunneling events, is shown to be directly related to the power law exponent in the measured current-voltage characteristics. We discuss the implications of these findings in light of models on cotunneling and hopping transport in mesoscopic, granular conductors.