  Pulse distortion, as one of the coherent error sources, hinders the
characterization and control of qubits. In the semiconductor quantum dot
system, the distortions on measurement pulses and control pulses disturb the
experimental results, while no effective calibration procedure has yet been
reported. Here, we demonstrate two different calibration methods to calibrate
and correct the distortion using the two-qubit system as a detector. The two
calibration methods have different correction accuracy and complexity. One is
the coarse predistortion (CPD) method, with which the distortion is partly
relieved. The other method is the all predistortion (APD) method, with which we
measure the transfer function and significantly improve the exchange
oscillation homogeneity. The two methods use the exchange oscillation
homogeneity as the metric and are appropriate for any qubit that oscillates
with a diabatic pulse. With the APD procedure, an arbitrary control waveform
can be accurately delivered to the device, which is essential for
characterizing qubits and improving gate fidelity.
