SQMS Center

Science Highlights

Oxygen Vacancies in Niobium Pentoxide: A Key Source of Loss in Nb Superconducting Qubits

SQMS researchers uncover loss mechanisms in the surface oxide, paving the way for mitigation strategies to enhance qubit performance.

Silicon Surface Modification Improves Qubit Performance

SQMS researchers find changing standard acid treatment can improve qubit performance, and this result gives clues that point toward the sources of two-level systems losses.

Quasiparticle Spectroscopy from Superfluid Density Measurements

Precision measurements of the London penetration depth in devices provide access to low-energy states inside the superconducting gap, which are the major fingerprints of quantum decoherence.

Identifying and Mitigating Fabrication-Induced Losses in Superconducting Quantum Devices

SQMS researchers characterize niobium hydride formation from wet chemical processing and associated noise sources in superconducting devices for quantum information science applications

Faster Gates and Reduced Crosstalk on a new 2D QPU Architecture

A simple and scalable architecture to achieve high operation accuracy can be achieved using faster entangling gates

Deepest Sensitivity to Wavelike Dark Photon Dark Matter with SRF Cavities

Fermilab’s expertise in superconducting radiofrequency cavities leads to extremely sensitive dark matter detectors, an order of magnitude more sensitive than previous efforts.

Direct Measurement of Microwave Loss in Nb Films for Superconducting Qubits

Microwave dissipation in niobium films resembles that of record-high intrinsic quality factor of bulk niobium SRF cavities within the quantum regime.

Revealing why Tantalum Oxide is Less Lossy than Niobium Oxides

SQMS scientists unravel the structural difference and formation mechanism of tantalum and niobium oxides in superconducting qubits

Uncovering Loss Mechanisms in High-Resistivity Silicon for Quantum Devices with Parts-per-Billion Precision

New insights into the origins of loss in a commonly used superconducting qubit substrate help to develop mitigation strategies for improved qubit coherence

Correlating Structural Imperfections and Resonator Performance

SQMS scientists explore how fabrication methods affect the microstructure and performance of superconducting coplanar waveguide resonators

AI meets Quantum: Optimal Gate Compilation using Reinforcement Learning

Harnessing reinforcement learning to optimize quantum state preparation and gate compilation, achieving high-fidelity results even in noisy environments

Doubling Photon Lifetime by Interconnecting Superconducting Radiofrequency (SRF) Cavities 

Manipulating the phase on a coaxial cable may enable doubling of the coherence time

Saving Qubits from Lossy Oxides

Unique qubit fabrication technique enables systematic improvements in performance of superconducting devices for quantum computing, communication, and sensing

Identifying Potential Nanoscale Sources of Decoherence in Nb Superconducting Qubits

Insights regarding defects in the surface oxide help inform new methods for improving qubit coherence 

Disentangling the Sources of Ionizing Radiation in a Typical Qubit Chip

Identifying the sources of radioactivity enables the development of appropriate strategies for their mitigation

Benchmarking Variational Quantum Eigensolvers for the Kitaev Model

Advancing variational quantum algorithms on NISQ devices

Stabilizing and Improving Qubit Coherence by Engineering Noise Spectrum of Two-Level Systems 

Novel protocols reduce qubit noise and stabilize coherence times by engineering the noise spectrum of two-level systems, offering a complementary approach to improving quantum computing performance.

Probing Superconducting State Properties of Nb Films used in Superconducting Qubits

Studying superconducting state properties reveals material imperfections limiting qubit coherence 

On the Hunt for Dark Matter with Entangled Haloscopes

Exploring the role of entanglement for next-generation detector technology, with applications to fundamental physics