13 citations · 26 across the 11 of their papers we have counts for
11 papers
Evidence for a low-gap component in compressively stressed niobium thin films
J. T. Paustian, Maciej Olszewski, Kiichi Okubo +6
We investigate the microwave response of sputtered Nb films as a function of biaxial film stress. Although transport measurements show nearly identical superconducting transition t…
Fabrication-free assessment of microwave losses in germanium-based dielectrics and superconductors
Haoran Lu, Kushagra Aggarwal, Xiangqin Wang +10
We present a flip-chip-based sensing scheme to measure effective microwave losses associated with target materials for quantum technologies, without requiring any device fabricatio…
Imaging Harmonic Generation of Magnons
Anthony J. D'Addario, Kwangyul Hu, Maciej W. Olszewski +4
This work combines theory and experiment to examine the mechanisms underlying the harmonic generation of magnons. We develop a nonlinear spin-wave framework that is directly analog…
Fabrication effects on Niobium oxidation and surface contamination in Niobium-metal bilayers using X-ray photoelectron spectroscopy
Tathagata Banerjee, Maciej W. Olszewski, Valla Fatemi
Superconducting resonators and qubits are limited by dielectric losses from surface oxides. Surface oxides are mitigated through various strategies such as the addition of a metal…
Krypton-sputtered tantalum films for scalable high-performance quantum devices
Maciej W. Olszewski, Lingda Kong, Simon Reinhardt +9
Superconducting qubits based on tantalum (Ta) thin films have demonstrated the highest-performing microwave resonators and qubits. This makes Ta an attractive material for supercon…
Spectroscopy and Coherent Control of Two-Level System Defect Ensembles Using a Broadband 3D Waveguide
Qianxu Wang, Juan S. Salcedo-Gallo, Salil Bedkihal +4
Defects in solid-state materials play a central role in determining coherence, stability, and performance in quantum technologies. Although narrowband techniques can probe specific…
Active-Learning Inspired Theory-Experiment Loop Approach for Management of Material Defects: Application to Superconducting Qubits
Sarvesh Chaudhari, Cristóbal Méndez, Rushil Choudhary +11
Surface oxides are associated with two-level systems (TLSs) that degrade the performance of niobium-based superconducting quantum computing devices. To address this, we introduce a…
Low barrier ZrO-based Josephson junctions
Jaehong Choi, Maciej Olszewski, Luojia Zhang +8
The Josephson junction is a crucial element in superconducting devices, and niobium is a promising candidate for the superconducting material due to its large energy gap relative t…
Low-loss Nb on Si superconducting resonators from a dual-use spintronics deposition chamber and with acid-free post-processing
Maciej W. Olszewski, Jadrien T. Paustian, Tathagata Banerjee +13
Magnetic impurities are known to degrade superconductivity. For this reason, physical vapor deposition chambers that have previously been used for magnetic materials have generally…
Rotational transition, domain formation, dislocations and defects in vortex systems with combined six- and 12-fold anisotropic interactions
M. W. Olszewski, M. R. Eskildsen, C. Reichhardt +1
We introduce a new model for a pairwise repulsive interaction potential of vortices in a type-II superconductor, consisting of superimposed six- and 12-fold anisotropies. Using num…
Structural Transitions in Vortex Systems with Anisotropic Interactions
M. W. Olszewski, M. R. Eskildsen, C. Reichhardt +1
We introduce a model of vortices in type-II superconductors with a four-fold anisotropy in the vortex-vortex interaction potential. Using numerical simulations we show that the vor…