Removal of spurious microwave modes via flip-chip crossover
A coplanar waveguide device includes a coplanar waveguide structure disposed on a substrate, at least one qubit coupled to the coplanar waveguide structure and an add-on chip having a metallized trench, and disposed over the substrate.
1. A coplanar waveguide (CPW) device, comprising:
a first chip including a patterned CPW; and
a second chip disposed on the first chip, the second chip having a metallized trench that removes spurious microwave modes from the first chip;
wherein the second chip is configured as a cap over the first chip, the second chip further comprising a first surface and a second surface opposite the first surface such that the first surface includes the metallized trench, and the second surface includes a control signal line that passes through a thickness of the second chip and extends between an opening in the metallized trench so as to provide a control signal to the patterned CPW.
2. The device as claimed in claim 1 wherein the patterned CPW is disposed on a substrate.
3. The device as claimed in claim 2 further comprising at least one qubit coupled to the patterned CPW.
4. The device as claimed in claim 2 wherein the patterned CPW comprises:
a resonator;
a drive pad coupled to the resonator; and
a qubit pocket coupled to the resonator.
5. The device as claimed in claim 4 further comprising a qubit disposed in the qubit pocket.
6. The device as claimed in claim 5 wherein the drive pad is configured to drive the qubit at a pre-defined frequency.
7. The device as claimed in claim 3 wherein the patterned CPW supports a pre-defined drive frequency for the qubit.
8. The device as claimed in claim 7 wherein the patterned CPW supports spurious microwave modes.
9. The device as claimed in claim 8 wherein the metallized trench is configured to remove the spurious microwave modes.