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Building on the previous results of the Weyl chamber steering method, wedemonstrate how to generate high-fidelity controlled-not by direct applicationof certain, physically relevant Hamiltonians with fixed coupling constantscontaining Rabi terms. Such Hamiltonians are often used to describe twosuperconducting qubits driven by local rf-pulses.  It is found that in order to achieve 100% fidelity in a system withcapacitive coupling of strength g one Rabi term suffices. We give the exactvalues of the physical parameters needed to implement such CNOT. The gate timeand all possible Rabi frequencies are found to be t=pi/(2g) and Omega_1/g =sqrt(64n^2-1), n=1,2,3,... .  Generation of a perfect CNOT in a system with inductive coupling,characterized by additional constant k, requires the presence of both Rabiterms. The gate time is again t = pi/(2g), but now there is an infinite numberof solutions, each of which is valid in a certain range of k and ischaracterized by a pair of positive integers (n,m). We distinguish two cases,depending on the sign of the coupling constant:  (1) the antiferromagnetic case (k>=0);  (2) the ferromagnetic case (k<=0).  The paper concludes with consideration of fidelity degradation by switchingto resonance. Simulation of time-evolution based on the 4th order Magnusexpansion reveals characteristics of the gate similar to those found in theexact case, with slightly shorter gate time and shifted values of Rabifrequencies.Comment: 14 pages, 1 figure (select PostScript to view); minor corrections;  added Appendix: Derivation of the Hamiltonian for inductively coupled flux  qubit

Generation of high-fidelity controlled-NOT logic gates by coupled superconducting qubits