Towards Tunable Transitions in 2-D Transmons

We have developed a design for a tunable transmon qubit with an on-chip flux bias. The transmon is fabricated with two sub-micron Al/AlO$_{x}$/Al tunnel junctions and coupled to a superconducting planar lumped-element resonator. A coplanar transmission line provides flux coupling and tuning of the qubit's transition energies. We will discuss the design and fabrication strategy and present preliminary measurements of coherence and tunability in these devices.