  Faster and more precise physical processing of quantum gate, by suitably
designing a pulse sequence to implement the target gate, will greatly improve
the performance of quantum algorithms in the presence of noise. In this paper,
we demonstrate that, by employing OpenPulse design kit for IBM Q devices, the
controlled-V gate (CV gate) can be implemented in about 34.5 % shorter gate
time, with 0.66 % improvement in the average gate fidelity, compared to the
standard version provided there. Then, based on the theory of Cartan
decomposition, we show that the performance of several two-qubit gates
containing CV gates can also be improved. Moreover, the average gate fidelity
of Toffoli gate can be improved to 96.16 % from 90.23 % achieved in the default
IBM Q package. These results imply the importance of our CV gate implementation
technique, which, as an additional option for the basis_gate set design, may
shorten the overall computation time and consequently improve the accuracy of
several quantum algorithms.
