Shot-noise characteristics of triple-barrier resonant-tunneling diodes

TL;DR

This study experimentally investigates shot noise in triple-barrier resonant-tunneling diodes, revealing unexpected noise reduction and enhancement behaviors linked to differential conductance, highlighting gaps in current theoretical understanding.

Contribution

The paper provides new experimental insights into shot noise behavior in triple-barrier diodes, showing larger-than-expected noise reduction and complex correlations with conductance.

Findings

Shot noise is reduced below Poissonian in positive differential conductance regimes.

Shot noise is enhanced above Poissonian in negative differential conductance regimes.

Results challenge existing semi-classical models of noise in heterostructures.

Abstract

We have found experimentally that the shot noise in InAlAs-InGaAs-InAlAs Triple-Barrier Resonant-Tunneling Diodes (TBRTD) is reduced over the 2eI Poissonian value whenever their differential conductance is positive, and is enhanced over 2eI when the differential conductance is negative. This behavior, although qualitatively similar to that found in double-barrier diodes, differs from it in important details. In TBRTDs the noise reduction is considerably larger than predicted by a semi-classical model, and the enhancement does not correlate with the strength of the negative differential conductance. These results suggest an incomplete understanding of the noise properties of multiple-barrier heterostructures.