Related papers: Nitrogen Plasma Passivated Niobium Resonators for …
Tantalum is a promising platform for superconducting quantum circuits, yet coherence times remain limited by dielectric losses from interfacial two-level systems (TLS), exacerbated by native oxide regrowth. Here, we implement molecular…
Interfacing superconducting microwave resonators with optical systems enables sensitive photon detectors, quantum transducers, and related quantum technologies. Achieving high optical pulse repetition is crucial for maximizing the device…
Lithium niobate is a promising material for developing quantum acoustic technologies due to its strong piezoelectric effect and availability in the form of crystalline thin films of high quality. However, at radio frequencies and cryogenic…
Superconducting thin films of niobium have been extensively employed in transmon qubit architectures. Although these architectures have demonstrated remarkable improvements in recent years, further improvements in performance through…
The high critical magnetic field and relatively high critical temperature of niobium nitride (NbN) make it a promising material candidate for applications in superconducting quantum technology. However, NbN-based devices and circuits are…
Scaling up superconducting quantum processors requires a high routing density for readout and control lines, relying on low-loss interconnects to maintain design flexibility and device performance. We propose and demonstrate a universal…
Nitrogen doping treatment with the subsequent electropolishing (EP) of the niobium superconducting cavity can significantly increase the cavity's quality factor up to a factor of 3. But the process of the EP removal may reintroduce hydrogen…
The performance of superconducting radio-frequency (SRF) cavities made of Niobium is tied to the quality of their inner surfaces exposed to the radio frequency (RF) waves. Future superconducting particle accelerators, because of their…
The radio-frequency surface resistance of niobium resonators is incredibly reduced when nitrogen impurities are dissolved as interstitial in the material, conferring ultra-high Q-factors at medium values of accelerating field. This effect…
Niobium nitride (NbN) is a metallic superconductor that is widely used for superconducting electronics due to its high transition temperature ($T_c$) and kinetic inductance. Processing-induced damage negatively affects the performance of…
We report the rf performance of a single-cell superconducting radiofrequency cavity after low temperature baking in a nitrogen environment. A significant increase in quality factor has been observed when the cavity was heat treated in the…
A detailed study of the near-surface structure and composition of Nb, the material of choice for Superconducting Radio Frequency accelerator (SRF) cavities, is of great importance in order to understand the effects of different treatments…
Niobium is commonly used for superconducting quantum systems as readout resonators, capacitors, and interconnects. The coherence time of the superconducting qubits is mainly limited by microwave dissipation attributed to two-level system…
The performance of superconducting microwave circuits is strongly influenced by the material properties of the superconducting film and substrate. While progress has been made in understanding the importance of surface preparation and the…
We present an experimental characterisation of the electrical properties of 3D-printed Niobium. The study was performed by inserting a 3D-printed Nb post inside an Aluminium cylindrical cavity, forming a 3D lumped element re-entrant…
Vacuum thermal treatments (baking) are known to improve the superconducting properties of the RF surface layer of niobium cavities, and are employed as a last processing step to increase their efficiency determined by intrinsic quality…
Characterizing superconducting microwave resonators with highly dissipative elements is a technical challenge, but a requirement for implementing and understanding the operation of hybrid quantum devices involving dissipative elements, e.g.…
Performance of superconducting resonators, particularly cavities for particle accelerators and micro cavities and thin film resonators for quantum computations and photon detectors has been improved substantially by recent materials…
The fabrication of superconducting circuits requires multiple deposition, etch and cleaning steps, each possibly introducing material property changes and microscopic defects. In this work, we specifically investigate the process of argon…
Nitrogen vacancy (NV) centers in diamond have emerged in recent years as leading quantum sensors in various modalities. Most applications benefit from shallow NVs, enabling higher sensitivity and resolution. However, near surface NVs ($<$…