Hybrid Josephson junction-based quantum devices in magnetic field

The technology of quantum computing is believed to solve certain computational problems significantly faster than classical computers, enabling classically inaccessible problems. However, the technology is still in its infancy and it is still too early to conclude which physical system(s) will form the basis of tomorrow's quantum computer. Small...

Magnetic-field-compatible superconducting transmon qubit

We present a hybrid semiconductor-based superconducting qubit device that remains coherent at magnetic fields up to 1 T. The qubit transition frequency exhibits periodic oscillations with the magnetic field, consistent with interference effects due to the magnetic flux threading the cross section of the proximitized semiconductor nanowire...

Observation of Vanishing Charge Dispersion of a Nearly Open Superconducting Island

Isolation from the environment determines the extent to which charge is confined on an island, which manifests as Coulomb oscillations, such as charge dispersion. We investigate the charge dispersion of a nanowire transmon hosting a quantum dot in the junction. We observe rapid suppression of the charge dispersion with increasing junction...

Magnetic-Field-Resilient Superconducting Coplanar-Waveguide Resonators for Hybrid Circuit Quantum Electrodynamics Experiments

Superconducting coplanar-waveguide resonators that can operate in strong magnetic fields are important tools for a variety of high-frequency superconducting devices. Magnetic fields degrade resonator performance by creating Abrikosov vortices that cause resistive losses and frequency fluctuations or suppress the superconductivity entirely. To...

Magnetic field compatible circuit quantum electrodynamics with graphene Josephson junctions

Circuit quantum electrodynamics has proven to be a powerful tool to probe mesoscopic effects in hybrid systems and is used in several quantum computing (QC) proposals that require a transmon qubit able to operate in strong magnetic fields. To address this we integrate monolayer graphene Josephson junctions into microwave frequency...