Spin qubits in multielectron quantum dots

Abstract

We study the effect of mesoscopic fluctuations on the magnitude of errors\nthat can occur in exchange operations on quantum dot spin-qubits. Mid-size\ndouble quantum dots, with an odd number of electrons in the range of a few tens\nin each dot, are investigated through the constant interaction model using\nrealistic parameters. It is found that the constraint of having short pulses\nand small errors implies keeping accurate control, at the few percent level, of\nseveral electrode voltages. In practice, the number of independent parameters\nper dot that one should tune depends on the configuration and ranges from one\nto four.\n