Manipulation of Pauli spin blockade in double quantum dot systems.

Pauli spin blockade (PSB) is a significant physical effect in double quantum dot (DQD) systems. In this paper, we start from the fundamental quantum model of the DQD with the electron-electron interaction being considered and then systematically study the PSB effect in DQD by using a recently developed nonperturbative method, the hierarchical equations of motion approach. By checking the current-voltage and nonequilibrium spectral function features, the physical picture of the PSB is explicitly elucidated. Then, various kinds of manipulation of PSBs are discussed, including gate voltage, exchange interaction, and electron spin resonance. Three main characteristics beyond low-order perturbation theory are demonstrated in detail as follows: (1) the finite leakage current in the strongly correlated limit; (2) the enhancement and lifting of PSB by exchange interaction; and (3) the ON-and-OFF switch of PSB by real-time modulation.