The signature of a double quantum-dot structure in the I-V characteristics of a complex system

TL;DR

This paper presents a method to identify whether a complex quantum system contains one or multiple quantum dots by analyzing temperature-dependent I-V characteristics, aiding in structural determination.

Contribution

It introduces a novel approach based on orthodox theory to distinguish single-dot from double-dot systems through I-V analysis, applicable across various resistance, capacitance, and temperature ranges.

Findings

Able to differentiate single and double quantum-dot structures from I-V data.

Method accounts for different resistance, capacitance, and temperature conditions.

Provides a way to infer system structure without direct imaging.

Abstract

We demonstrate that by carefully analyzing the temperature dependent characteristics of the I-V measurements for a given complex system it is possible to determine whether it is composed of a single, double or multiple quantum-dot structure. Our approach is based on the orthodox theory for a double-dot case and is capable of simulating I-V characteristics of systems with any resistance and capacitance values and for temperatures corresponding to thermal energies larger than the dot level spacing. We compare I-V characteristics of single-dot and double-dot systems and show that for a given measured I-V curve considering the possibility of a second dot is equivalent to decreasing the fit temperature. Thus, our method allows one to gain information about the structure of an experimental system based on an I-V measurement.