Full Counting Statistics In Side-coupled T Shaped Double Quantum Dots

Based on the method of particle-number-resolved quantum master equation, the full counting statistics of the electrons through side-coupled double quantum dots system is investigated. Firstly, we analyze the effect of the quantum coherence on the full counting statistics of the electrons through the system. When the strength of the tunneling coupling between the two quantum dots is weaker than that between the quantum dot and two electrodes, the noise mainly decided by coherent effects of electrons tunneling through two different paths, that is to say, the non-diagonal elements of the reduced density matrix play a major role. Moreover, when the ratio J/Γis less than a certain value (about 1/3), the super-Poissonian noise is observed, which can be explained by the fast and slow transport channels. With the tunneling coupling strength between the dots being strong, the impact of quantum coherence effect on electronic full-counting statistics becomes weak gradually. Secondly, how the ground state of system affecting the full-counting statistics is studied. With the corresponding to the first current steps formed by the transfer of the system from the single-electron-occupied eigenstate to the zero occupied eigenstate, or by the transfer of the system from the double-electron-occupied eigenstate to the single-electron-occupied eigenstate, the current shot noise can appear the super-Poissonian distribution. This can also be explained by the fast and slow transport channel.