Analysis of electrostatic interaction between a charge trap and a quantum dot based single electron transistor

In this article, we studied the effect of a single charge trap on the charge stability diagram of a quantum dot-based single electron transistor. The anomalies in the Coulomb characteristic diagram of the quantum dot, system energy, occupation probabilities, and conductivity of the quantum dot have been investigated. These anomalies are caused by the electrostatic interaction of the quantum dot with the charge trap. The trap is capacitively connected to the quantum dot and can be empty or occupied by an electron; considering a few quantum states of the system, we solved the master equation using Fermi's golden rule to obtain the tunneling rates and the matrix of tunneling coefficients. Then, calculating the inverse of the matrix of coefficients, the probability of each quantum state has been obtained. Validation of the analysis is performed by comparing the simulation results with the experimental data. Finally, we have demonstrated that our study provides a tool to detect the charge presence in a trap near a quantum dot, which can potentially be used for the readout of quantum gates.