Cumulant properties of topological superconductor coupled single quantum dot structures

This paper utilizes the quantum master equation in particle number representation and calculates the characteristic polynomial of the Liouville superoperator to study the properties of various order cumulants of full counting statistics in a single quantum dot coupled with a topological superconducting nanowire structure. The results show that the cumulants exhibit a step-like distribution with voltage, the cumulative amount of each order increases when the voltage is twice the energy difference between different parity levels of the system; the sum of the first-order cumulants of each sub-channel equals the total current of all channels, but the interference between energy levels leads to non-trivial addition rules for higher-order cumulants between sub-channels and the total channel. When quantum dots and nanowires are weakly coupled at the remote end, Majorana zero modes are more likely to appear, and Majorana zero modes can participate in transport through lower energy levels; The Coulomb interaction alters the degeneracy state of energy levels, thereby changing the number of steps in the voltage-dependent cumulants.