123 citations · 155 across the 10 of their papers we have counts for
12 papers
Microwave dielectric properties of LiNbO and AlN at millikelvin temperatures and single-photon power
Alessandro Reineri, Francesco Crisa, Akshay Murthy +8
Efficient bidirectional microwave-optical photon conversion is a key capability for scaling superconducting quantum processors into distributed networks. However, achieving the nec…
Optimizing Superconducting Nb Film Cavities by Mitigating Medium-Field Q-Slope Through Annealing
B. Abdisatarov, G. Eremeev, H. E. Elsayed-Ali +9
Niobium films are of interest in applications in various superconducting devices, such as superconducting radiofrequency cavities for particle accelerators and superconducting qubi…
Demonstrating magnetic field robustness and reducing temporal T1 noise in transmon qubits through magnetic field engineering
Bektur Abdisatarov, Tanay Roy, Daniel Bafia +10
The coherence of superconducting transmon qubits is often disrupted by fluctuations in the energy relaxation time (T1), limiting their performance for quantum computing. While back…
Ultracoherent superconducting cavity-based multiqudit platform with error-resilient control
Taeyoon Kim, Tanay Roy, Xinyuan You +26
Realizing the promise of quantum computing requires simultaneously increasing Hilbert-space size and coherence times. While qubit-based architectures have long been the dominant pa…
Quantifying Trapped Magnetic Vortex Losses in Niobium Resonators at mK Temperatures
D. Bafia, B. Abdisatarov, R. Pilipenko +4
Trapped magnetic vortices in niobium introduce microwave losses that degrade the performance of superconducting resonators. While such losses have been extensively studied above 1~…
Direct Measurement of Microwave Loss in Nb Films for Superconducting Qubits
B. Abdisatarov, D. Bafia, A. Murthy +9
Niobium films are a key component in modern two-dimensional superconducting qubits, yet their contribution to the total qubit decay rate is not fully understood. The presence of di…
Systematic Improvements in Transmon Qubit Coherence Enabled by Niobium Surface Encapsulation
Mustafa Bal, Akshay A. Murthy, Shaojiang Zhu +37
We present a novel transmon qubit fabrication technique that yields systematic improvements in T relaxation times. We fabricate devices using an encapsulation strategy that inv…
High quality superconducting Nb co-planar resonators on sapphire substrate
S. Zhu, F. Crisa, M. Bal +10
We present measurements and simulations of superconducting Nb co-planar waveguide resonators on sapphire substrate down to millikelvin temperature range with different readout powe…
Key directions for research and development of superconducting radio frequency cavities
S. Belomestnykh, S. Posen, D. Bafia +53
Radio frequency superconductivity is a cornerstone technology for many future HEP particle accelerators and experiments from colliders to proton drivers for neutrino facilities to…
Oxygen Vacancies in Niobium Pentoxide as a Source of Two-Level System Losses in Superconducting Niobium
Daniel Bafia, Akshay Murthy, Anna Grassellino +1
We identify a major source of quantum decoherence in three-dimensional superconducting radio-frequency (SRF) resonators and two-dimensional transmon qubits composed of oxidized nio…
Discovery of Nb hydride precipitates in superconducting qubits
Jaeyel Lee, Zuhawn Sung, Akshay A. Murthy +3
We report the first evidence of the formation of niobium hydrides within niobium films on silicon substrates in superconducting qubits fabricated at Rigetti Computing. We combine c…
Signatures of Enhanced Superconducting Properties in Niobium Cavities
D. Bafia, A. Grassellino, M. Checchin +2
Superconducting radio-frequency (SRF) niobium cavities are critical for modern particle accelerators, as well as for advancing superconducting quantum systems and enabling ultra-se…