Fermi-edge Singularity in II-VI Semiconductor Resonant Tunneling Structures

TL;DR

This paper reports the observation of Fermi-edge enhanced resonant tunneling in a II-VI semiconductor heterostructure with quantum dots, revealing many-particle effects and complex behaviors not fully explained by existing theory.

Contribution

It provides experimental evidence of Fermi-edge singularity effects in II-VI heterostructures and highlights limitations of current theoretical models in describing detailed tunneling features.

Findings

Resonant tunneling persists up to 45 K

Enhanced tunneling due to many-particle effects observed

Fine structure indicates limitations of existing Fermi edge theory

Abstract

We report on the observation of Fermi edge enhanced resonant tunneling transport in a II-VI semiconductor heterostructure. The resonant transport through a self assembled CdSe quantum dot survives up to 45 K and probes a disordered two dimensional (2D) like emitter which dominates the magnetic field dependence of the transport. An enhancement of the tunnel current through many particle effects is clearly observable, even without an applied magnetic field. Additional fine structure in the tunneling current suggests that while conventional Fermi edge singularity theory successfull reproduces the general features of the increased transmission, it is not adequate to describe all details of the current enhancement.