Initialization, manipulation, and readout of chiral qubits by bias and inhomogeneous Zeeman field in triangular triple quantum dots

We realize the initialization, manipulation, and readout of qubits in triangular triple quantum dots (TTQDs) with theoretical and numerical simulation calculations. In the initialization, the degenerate ground states can be split by adding a vertical magnetic flux or a bias voltage at the initial time. This is consistent with the magnetoelectric equivalence proposed in previous work, and both cause chiral state splitting. In the manipulation, we add an inhomogeneous Zeeman field to the TTQDs. Based on the Heisenberg model of the two-level system, it is obtained that the applied Zeeman field gradient will cause Rabi oscillation of the two chiral states' occupation probability, which also corresponds to the manipulation of chiral qubits on the Bloch sphere. The Rabi cycle and amplitude vary with the gradient of the Zeeman field and the internal chiral term, and numerical simulation is consistent with the theoretical results. Finally, we give a possible readout method to use for the topological blockage of chiral and conduction current. This method provides an alternative idea for qubits, which can realize quantum coding by using the smallest chiral topological structure.