Fermi edge singularity in II–VI semiconductor resonant tunneling structures

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.

Counting statistics of transport through Coulomb blockade nanostructures: High-order cumulants and non-Markovian effects

“…53. Additionally, the non-Markovian correction due to strong spectral features in the Fermi edge singularity problem [128][129][130]132 is responsible for the observed discrepancy 131 between the measured Fano factor and the expected result based on the Markovian part only. A more detailed account of this problem will be presented elsewhere.…”

Scaling of the Fermi‐Edge Singularity in Quantum Dots

“…For a high charge carrier concentration the bending is rather weak and the lead forms a three‐dimensional (3D) system (see Figure d) while for the other case the bending is strong and a two‐dimensional (2D) lead is formed (see Figure e). For transport experiments using self‐assembled InAs quantum dots both the 3D leads and 2D leads have been realized individually.…”

“…Electron–electron interactions effects like Coulomb‐blockade and Fermi‐edge singularity (FES) have been observed by shot noise measurements . Further experiments about temperature and size dependence have been performed . Also samples with two coupled layers with self‐assembled InAs quantum dots have been studied both in magnetotransport and shot noise measurements …”

Semimagnetic II–VI semiconductor resonant tunneling diodes characterized by high-resolution X-ray diffraction

“…Semimagnetic resonant tunneling diodes (RTDs) are of profound fundamental interest since they allow control of the spin orientation of tunneling electrons by an applied voltage rather than a magnetic field [1][2][3], and to study quantum transport in 2D and 0D systems in magnetic and nonmagnetic environments [4]. Spin dependent transport in such devices is based on resonant tunneling through quantized states in a semimagnetic quantum well or quantum dot with large spin splitting due to sp-d exchange interaction [5].…”