PNNL

Christian Boutan is a hands-on experimental physicist with experience in axion dark matter physics, quantum sensing, low-temperature instrumentation, radio-frequency engineering, and digital/analog circuits. Boutan has been a key member of the Axion Dark Matter eXperiment (ADMX) collaboration since 2011, and was part of the core team that built and commissioned the U.S. Department of Energy’s "Gen 2" flagship direct-detection axion dark matter experiment that set the world’s first limits on Dine-Fischler-Srednicki-Zhitnitsky axions.

In 2014, Boutan spearheaded a secondary high-frequency pathfinder axion search, the ADMX Sidecar, that set new limits on axion-photon coupling and doubled as an ADMX research and development platform for testing new technologies. He serves as the collaboration’s publications and presentations coordinator and chairs bi-weekly meetings devoted to designing future incarnations of the experiment.

Since accepting a position as a staff scientist, Boutan has focused on establishing Pacific Northwest National Laboratory (PNNL) as a leader in the axion physics field and on combining PNNL core strengths to grow a milikelvin microwave quantum sensing capability. With this new testbed, Boutan demonstrated the operation of superconducting qubits in 2022.

Boutan enjoys blazing trails, solving problems, learning new things, getting his hands dirty, and learning about our remarkable universe.

• Dark matter detection
• Quantum sensing
• Low-temperature physics
• Superconducting device characterization
• Machine learning
• Radio-frequency engineering

• PhD in physics, University of Washington
• MS in physics, University of Washington
• BS in physics, College of Charleston

• Institute of Electrical and Electronics Engineers, Richland, WA, Sensors chapter chair
• American Physical Society

• Early Career Research Program Award, High Energy Physics, U.S. Department of Energy (2023)
• Impact Core Value Award, National Security Directorate, Pacific Northwest National Laboratory (2022)
• Creativity Core Value Award, National Security Directorate, Pacific Northwest National Laboratory (2020)

• Protractor for calculating miter and bevel angles for installing molding, US patent# 7574813B1

2024

Bartram C., T. Braine, R. Cervantes, N. Crisosto, N. Du, C. Goodman, M. Guzzetti, et al. 2024. "Nonvirialized Axion Search Sensitive to the Doppler Effects in the Milky Way Halo." Physical Review D 109, no. 8:Art. No. 083014. PNNL-SA-195179. doi:10.1103/PhysRevD.109.083014

Boutan C.R., B.H. LaRoque, E.W. Lentz, N.S. Solomon-Oblath, M.S. Taubman, J.R. Tedeschi, J. Yang, et al. 2024. "Axion Dark Matter eXperiment: Run 1A Analysis Details." Physical Review D 109, no. 1:Art. No. 012009. PNNL-SA-185330. doi:10.1103/PhysRevD.109.012009

Chakrabarty S., J.R. Gleason, Y. Han, A.T. Hipp, M. Solano, P. Sikivie, N.S. Sullivan, et al. 2024. "Low Frequency (100 - 600 MHz) Searches with Axion Cavity Haloscopes." Physical Review D 109, no. 4:Art. No. 042004. PNNL-SA-186229. doi:10.1103/PhysRevD.109.042004

2023

Bartram C., T. Braine, R. Cervantes, N. Crisosto, N. Du, G. Leum, and P. Mohapatra, et al. 2023. "Dark Matter Axion Search Using a Josephson Traveling Wave Parametric Amplifier." Review of Scientific Instruments 94, no. 4:Art. No. 044703. PNNL-SA-168876. doi:10.1063/5.0122907

Boutan C., G. Carosi, L.J. Rosenberg, G. Rybka, K.M. Backes, C. Bartram, M. Baryakhtar, et al. 2023. “Axions beyond Gen 2.” International Journal of Modern Physics A, Vol. 38, No. 33n34, 2330012. doi:10.1142/S0217751X23300120

Chakrabarty S., et al. 2023. “Low Frequency (100-600 MHz) Searches with Axion Cavity Haloscopes.” arXiv preprint arXiv:2303.07116

Nitta T., T. Braine, N. Du, M. Guzzetti, C. Hanretty, G. Leum, L.J. Rosenberg, et al. 2023. "Search for a Dark-Matter-Induced Cosmic Axion Background with ADMX." Physical Review Letters 131, no. 10:Art. No. 101002. PNNL-SA-185846. doi:10.1103/PhysRevLett.131.101002

2022

Adams C.B., et al. 2022. “Axion Dark Matter.” arXiv preprint arXiv:2203.14923

Antypas D., et al. 2022. “New Horizons: Scalar and Vector Ultralight Dark Matter.” arXiv preprint arXiv:2203.14915

Grando M.B., C.R. Boutan, and J. Yang. 2022. “A Multiport Approach to Thermal Noise and Scattering Parameter Simulation of Cryogenic Experiments.” arXiv preprint arXiv:2209.04008

2021

Bartram C., T. Braine, E. Burns, R. Cervantes, N. Crisosto, N. Du, and H. Korandla, et al. 2021. "Search for Invisible Axion Dark Matter in the 3.3–4.2 µeV Mass Range." Physical Review Letters 127, no. 26:Art. No. 261803. PNNL-SA-168945. doi:10.1103/PhysRevLett.127.261803

Bartram C., T. Braine, R. Cervantes, N. Crisosto, N. Du, G. Leum, and L. Rosenberg, et al. 2021. "Axion Dark Matter Experiment: Run 1B Analysis Details." Physical Review D 103, no. 3:Article No. 032002. PNNL-SA-157407. doi:10.1103/PhysRevD.103.032002

Khatiwada R., D. Bowring, A.S. Chou, A. Sonnenschein, W. Wester, D.V. Mitchell, and T. Braine, et al. 2021. "Axion Dark Matter eXperiment: Detailed design and operations." Review of Scientific Instruments 92, no. 12:Art. No. 124502. PNNL-SA-154970. doi:10.1063/5.0037857

2020

Braine T., R. Cervantes, N. Crisosto, N. Du, S. Kimes, L. Rosenberg, and G.A. Rybka, et al. 2020. "Extended Search for the Invisible Axion with the Axion Dark Matter Experiment." Physical Review Letters 124, no. 10:Article No. 101303. PNNL-SA-151942. doi:10.1103/PhysRevLett.124.101303

2018

Boutan C.R., A.M. Jones, B.H. LaRoque, N.S. Solomon-Oblath, R. Cervantes, N. Du, and N. Force, et al. 2018. "Piezoelectrically Tuned, Multimode Cavity Search for Axion Dark Matter." Physical Review Letters 121, no. 26:Article No. 261302. PNNL-SA-137513. doi:10.1103/PhysRevLett.121.261302

Du N., N. Force, R. Khatiwada, E. Lentz, R. Ottens, L. Rosenberg, and G. Rybka, et al. 2018. "Search for invisible Axion Dark Matter with the Axion Dark Matter Experiment." Physical Review Letters 120, no. 15:151301. PNNL-SA-131328. doi:10.1103/PhysRevLett.120.151301

2017

Boutan, C. 2017. “A piezoelectrically tuned RF-cavity search for dark matter axions.” Ph.D. diss., University of Washington, https://www.proquest.com/dissertations-theses/piezoelectrically-tuned-rf-cavity-search-dark/docview/1886474732/se-2

2016

Hoskins J., et al. 2016. “Modulation sensitive search for nonvirialized dark-matter axions.” Physical Review D 94, no. 8: 082001. doi: 10.1103/PhysRevD.94.082001

Sloan J.V., et al. 2016. “Limits on axion–photon coupling or on local axion density: Dependence on models of the Milky Way’s dark halo.” Physics of the Dark Universe 14, 95-102, doi:10.1016/j.dark.2016.09.003