  Superconducting qubits with tunable coupling are ideally suited for fast and
accurate implementation of quantum logic. Here we present a simple approach,
based on Weyl chamber steering, to CNOT gate design for inductively coupled
phase qubits with tunable coupling strength g. In the presence of simultaneous
rf pulses on the individual qubits that appropriately track the coupling
strength as it is varied, we show that an infinite family of switching
sequences preserving the time integral or "area" of g can be used to generate
CNOT logic. We demonstrate our approach by considering time-dependencies most
likely to be used in actual implementations: trapezoidal, sine, and soft
quartic (also known as Landau's hat).
