Controlling the conductance and noise of driven carbon-based Fabry-Perot devices

TL;DR

This paper investigates how ac gating influences conductance and noise in carbon nanotube Fabry-Perot devices, revealing phase-sensitive effects and frequency-dependent conductance suppression or revival.

Contribution

It demonstrates the control of conductance interference and noise behavior in carbon nanotube devices through ac gating, highlighting phase sensitivity and frequency-specific responses.

Findings

Conductance interference can be suppressed or revived by tuning ac gate intensity.

Noise behavior depends on frequency, matching even multiples of the level spacing.

Conductance remains unaffected at frequencies that are integer multiples of the level spacing.

Abstract

We report on ac transport through carbon nanotube Fabry-Perot devices. We show that tuning the intensity of the ac gating induces an alternation of suppression and partial revival of the conductance interference pattern. For frequencies matching integer multiples of the level spacing of the system $\Delta$ the conductance remains irresponsive to the external field. In contrast, the noise in the low bias voltage limit behaves as in the static case only when the frequency matches an even multiple of the level spacing, thereby highlighting its phase sensitivity in a manifestation of the wagon-wheel effect in the quantum domain.