Spin qubit transport in a double quantum dot

Long distance spin communication is a crucial ingredient to scalable quantum computer architectures based on electron spin qubits.~ One way to transfer spin information over a long distance on chip is via electron transport.~ Here we study the transport of an electron spin qubit in a double quantum dot by tuning the interdot detuning voltage.~ We identify a parameter regime where spin relaxation hot-spots can be avoided and high-fidelity spin transport is possible. Within this parameter space, the spin transfer fidelity is determined by the operation speed and the applied magnetic field.~ In particular, near zero detuning, a proper choice of operation speed is essential to high fidelity. In addition, we also investigate the modification of the effective g-factor by the interdot detuning, which could lead to a phase error between spin up and down states. The results presented in this work could be a useful guidance for experimentally achieving high-fidelity spin qubit transport.