Transport through a double barrier in Large Radius Carbon Nanotubes in the presence of a transverse magnetic field

TL;DR

This paper investigates how a transverse magnetic field influences electron transport in large radius carbon nanotubes, revealing a reduction in critical exponents and predicting conductance peaks related to magnetic flux quantization.

Contribution

It provides new insights into the magnetic field effects on Luttinger Liquid behavior and transport through quantum dots in large radius carbon nanotubes, including experimental agreement and novel conductance predictions.

Findings

Magnetic field reduces the bulk critical exponent for tunneling density of states.

Predicted conductance peaks related to magnetic flux quantization.

Power-law temperature dependence of conductance maxima, influenced by magnetic field.

Abstract

We discuss the Luttinger Liquid behaviour of Large Radius Carbon Nanotube e.g. the Multi Wall ones (MWNT), under the action of a transverse magnetic field $B$. Our results imply a reduction with $B$ in the value of the $bulk$ critical exponent, $\alpha_{bulk}$, for the tunneling density of states, which is in agreement with that observed in transport experiments. Then, the problem of the transport through a Quantum Dot formed by two intramolecular tunneling barriers along the MWNT, weakly coupled to Tomonaga-Luttinger liquids is studied, including the action of a strong transverse magnetic field $B$. {We predict the presence of some peaks in the conductance G versus $B$, related to the magnetic flux quantization in the ballistic regime (at a very low temperature, $T$) and also at higher $T$, where the Luttinger behaviour dominates}. The temperature dependence of the maximum $G_{max}$ of the conductance peak according to the Sequential Tunneling follows a power law, $G\propto T^{\gamma_e-1}$ with $\gamma_e$ linearly dependent on the critical exponent, $\alpha_{end}$, strongly reduced by $B$.