activity
20182026
most citedSystematic Improvements in Transmon Qubit Coherence Enabled by Niobium Surface Encapsulation

123 citations · 248 across the 11 of their papers we have counts for

collaborators

13 papers

cond-mat.supr-con2026

Oxygen distribution and segregation at grain boundaries in Nb and Ta-encapsulated Nb thin films for superconducting qubits

Jaeyel Lee, Dieter Isheim, Zuhawn Sung +14

We report on atomic-scale analyses of oxygen distribution and segregation at grain boundaries (GBs) of Nb and Ta-encapsulated Nb (Ta/Nb) thin films for superconducting qubits using…

cond-mat.supr-con2025

Discovery of Niobium Hydride Precipitates in Superconducting Qubits

Zuhawn Sung, Daniel Bafia, Arely Cano +6

We report the evidence of the formation of niobium hydride phase within niobium films on silicon substrates in superconducting qubits fabricated at Rigetti Computing. For this stud…

quant-ph2025

Identifying Materials-Level Sources of Performance Variation in Superconducting Transmon Qubits

Akshay A. Murthy, Mustafa Bal, Michael J. Bedzyk +46

The Superconducting Materials and Systems (SQMS) Center, a DOE National Quantum Information Science Research Center, has conducted a comprehensive and coordinated study using super…

cond-mat.mtrl-sci2023★ 1 cited

Unveiling the nucleation and growth of Zr oxide precipitates of internally oxidized Nb3Sn superconductors

Jaeyel Lee, Zugang Mao, Dieter Isheim +2

We report on atomic-scale analyses of nucleation and growth of Zr oxide precipitates and the microstructural evolution of internally oxidized Nb3Sn wires for high-field superconduc…

cond-mat.mtrl-sci2023

First Direct Observation of Nanometer size Hydride Precipitations on Superconducting Niobium

Zu Hawn Sung, Arely Cano, Akshay Murthy +5

Superconducting niobium serves as a key enabling material for superconducting radio frequency (SRF) technology as well as quantum computing devices. At room temperature, hydrogen c…

cond-mat.mtrl-sci2023★ 1 cited

Selective thermal evolution of native oxide layer in Nb and Nb3Sn-coated SRF grade Nb: An in-situ angular XPS study

Arely Cano, Grigory V. Eremeev, Juan R. Zuazo +5

This contribution discusses the results of an in-situ angular XPS study on the thermal evolution of the native oxide layer on Nb3Sn and pure Nb. XPS data were recorded with convent…

quant-ph2023★ 123 cited

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…

cond-mat.supr-con2022

Stress-induced omega phase transition in Nb thin films for superconducting qubits

Jaeyel Lee, Zuhawn Sung, Akshay A. Murthy +2

We report the observation of omega phase formation in Nb thin films deposited by high-power impulse magnetron sputtering (HiPIMS) for superconducting qubits using transmission elec…

cond-mat.mes-hall2022

Developing a Chemical and Structural Understanding of the Surface Oxide in a Niobium Superconducting Qubit

Akshay A. Murthy, Paul Masih Das, Stephanie M. Ribet +11

Superconducting thin films of niobium have been extensively employed in transmon qubit architectures. Although these architectures have demonstrated remarkable improvements in rece…

quant-ph2021★ 3 cited

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…

cond-mat.supr-con2020★ 33 cited

Analysis of Magnetic Vortex Dissipation in Sn-Segregated Boundaries in NbSn Superconducting RF Cavities

Jared Carlson, Alden Pack, Mark K. Transtrum +9

We study mechanisms of vortex nucleation in NbSn Superconducting RF (SRF) cavities using a combination of experimental, theoretical, and computational methods. Scanning transmi…

cond-mat.mtrl-sci2019★ 47 cited

Grain-boundary structure and segregation in Nb3Sn coatings on Nb for high-performance superconducting radiofrequency cavity applications

Jaeyel Lee, Zugang Mao, Kai He +7

We report on atomic-scale analyses of grain boundary (GB) structures and segregation in Nb3Sn coatings on Nb, prepared by the vapor-diffusion process, for superconducting radiofreq…

cond-mat.mtrl-sci2018★ 40 cited

Atomic scale analysis of Nb3Sn on Nb prepared by a vapor-diffusion process for superconducting radiofrequency cavity applications

Jaeyel Lee, Sam Posen, Zugang Mao +5

We report an atomic-scale analysis of the microstructure of Nb3Sn coating on Nb prepared by vapor diffusion process for superconducting radiofrequency (SRF) cavity application usin…