Abstract
Several logical qubits and quantum gates have been proposed for semiconductor quantum dots controlled by voltages applied to top gates. The different schemes can be difficult to compare meaningfully. Here we develop a theoretical framework to evaluate disparate qubit-gating schemes on an equal footing. We apply the procedure to two types of double-dot qubits: the singlet-triplet (ST) and the semiconducting quantum dot hybrid qubit. We investigate three quantum gates that flip the qubit state: a DC pulsed gate, an AC gate based on logical qubit resonance (LQR), and a gate-like process known as stimulated Raman adiabatic passage (STIRAP). These gates are all mediated by an exchange interaction that is controlled experimentally using the interdot tunnel coupling and the detuning , which sets the energy difference between the dots. Our procedure has two steps. First, we optimize the gate fidelity () for fixed as a function of the other control parameters; this