papers

Publications (11)

quant-ph2026

Hardware-efficient erasure-error detection with an integer fluxonium

Junyoung An, Helin Zhang, Jeffrey M. Gertler +13

The paper demonstrates hardware‑efficient erasure‑error detection and conversion using an integer fluxonium qubit, showing improved state lifetimes and reduced gate errors by detec…

#quantum error correction#fluxonium qubits#erasure detection#mid-circuit measurement
quant-ph2026

Numerical Modeling of Quasiparticle-Induced Dissipation in Fluxonium Qubits

Kate Azar, Max Hays, Kyle Serniak

Nonequilibrium quasiparticles (QPs) generated by stray infrared and ionizing radiation can limit the performance of superconducting quantum processors and present challenges for qu…

quant-ph2025

ZZ-Free Two-Transmon CZ Gate Mediated by a Fluxonium Coupler

Junyoung An, Helin Zhang, Qi Ding +19

Eliminating residual ZZ interactions in a two-qubit system is essential for reducing coherent errors during quantum operations. In a superconducting circuit platform, coupling two…

quant-ph2025

Improving Transmon Qubit Performance with Fluorine-based Surface Treatments

Michael A. Gingras, Bethany M. Niedzielski, Kevin A. Grossklaus +21

Reducing materials and processing-induced decoherence is critical to the development of utility-scale quantum processors based on superconducting qubits. Here we report on the impa…

quant-ph2023

High-Fidelity, Frequency-Flexible Two-Qubit Fluxonium Gates with a Transmon Coupler

Leon Ding, Max Hays, Youngkyu Sung +16

We propose and demonstrate an architecture for fluxonium-fluxonium two-qubit gates mediated by transmon couplers (FTF, for fluxonium-transmon-fluxonium). Relative to architectures…

quant-ph2026

Characterization of Radiation-Induced Errors in Superconducting Qubits Protected with Various Gap-Engineering Strategies

H. Douglas Pinckney, Thomas McJunkin, Alan W. Hunt +26

Impacts from high-energy particles cause correlated errors in superconducting qubits by increasing the quasiparticle density in the vicinity of the Josephson junctions (JJs). Such…

quant-ph2024

Dephasing in Fluxonium Qubits from Coherent Quantum Phase Slips

Mallika T. Randeria, Thomas M. Hazard, Agustin Di Paolo +12

Phase slips occur across all Josephson junctions (JJs) at a rate that increases with the impedance of the junction. In superconducting qubits composed of JJ-array superinductors --…

quant-ph2025

Emergent Harmonics in Josephson Tunnel Junctions Due to Series Inductance

Junghyun Kim, Max Hays, Ilan T. Rosen +11

Josephson tunnel junctions are essential elements of superconducting quantum circuits. The operability of these circuits presumes a -periodic sinusoidal potential of a tunnel…

quant-ph2025

Temperature and Magnetic-Field Dependence of Energy Relaxation in a Fluxonium Qubit

Lamia Ateshian, Max Hays, David A. Rower +14

Noise from material defects at device interfaces is known to limit the coherence of superconducting circuits, yet our understanding of the defect origins and noise mechanisms remai…

quant-ph2026

Distinguishing types of correlated errors in superconducting qubits

Hannah P. Binney, H. Douglas Pinckney, Kate Azar +15

Errors in superconducting qubits that are correlated in time and space can pose problems for quantum error correction codes. Radiation from cosmic and terrestrial sources can incre…

quant-ph2026

Characterization and Comparison of Energy Relaxation in Fluxonium Qubits

Kate Azar, Lamia Ateshian, Mallika T. Randeria +19

Fluxonium superconducting qubits have demonstrated long coherence times and high single- and two-qubit gate fidelities, making them a favorable building block for superconducting q…