Speaker
Description
In recent years superconducting qubits have made huge strides in performance and quality. With improved qubit quality comes increasingly strict environmental requirements. One background of concern comes from black body radiation from higher temperature stages of the dilution refrigerator. IR photons are particularly challenging to shield from as many common RF materials are transparent to these photons, additionally these photons can efficiently slip through small cracks ($<$0.1mm). This can be rectified by incorporating a filtering structure directly into the flange of the device enclosure or shields. These filters are referred to as stub filters and allow for high suppression of high GHz and THz photons. Through careful optimization of enclosure seams, leakage into and out of the device package can be tuned and suppressed. An overview of flange stub filters as well as their implementation into qubit package will be shown. This solution is ideal considering high thermalization, radio purity, and vacuum compatibility, which are essential for highly suppressed environmental events. The form of these filters allow them to be well suited for a variety of quantum devices. Through these filters, rigorous environmental engineering efforts can be implemented to improve the performance of qubits.
