Patrick Strobeen - MIT

Wednesday 22 Apr 2026, 09:00 → 20:15 US/Eastern

IAMM

Patrick conducted his Ph.D. research at the University of Wisconsin, Madison under the supervision of Prof. Jason Kawasaki. His work focused on utilizing ultra-high vacuum thin film growth, spectroscopy, and microscopy techniques to investigate the atomic and chemical structure of metal / graphene / semiconductor structures during early stages (few monolayers) of thin film growth.

Afterwards, he joined the lab of Prof. Javad Shabani as a postdoctoral associate at New York University from early 2022 – late 2025 where he was interested in the thin film growth of superconducting germanium for use in merged-element superconducting devices.

Patrick joined EQuS at MIT in December of 2025 to further investigate materials-specific losses at interfaces within superconducting devices utilizing molecular beam epitaxy and in-situ spectroscopy techniques.

https://equs.mit.edu/patrick-strohbeen/

09:00 → 10:00 Research Meeting

Ride from hotel to IAMM

Speaker: Wonhee Ko (University of Tennessee, Knoxville)

10:00 → 10:20 Talk Prep

10:20 → 11:20 Materials-driven design of superconducting quantum devices

Superconducting quantum devices have undergone a massive renaissance since the first demonstration of the Cooper pair box in 1999 [1]. Utilizing the same general material structure (Al/AlOx/Al), much of the dramatic improvement over the past few decades is a direct result of better device engineering and design. However, studies and proposals challenging the standard materials paradigm of superconducting devices have become increasingly popular in recent years as a route towards improving the coherence of such devices. One of the more mature efforts has been to introduce alternative superconducting metals for the base metallization layer, namely Ta [2], replacing the more common Al and Nb metals used in modern devices. Yet, the continued reliance on the Al/AlOx/Al Josephson junction (JJ) remains a pain point, largely due to the lossy amorphous AlOx material and sensitivity of Al to aggressive chemical cleaning procedures.
Here, I will discuss some of the efforts I have pursued during my postdoctoral studies at New York University (NYU) in developing new materials for superconducting qubits to overcome long-standing issues that plague this technology. To this end, I developed a process of growing superconducting germanium thin films as a path towards epitaxial JJ structures integrated with group IV substrates [3]. A comprehensive structural, chemical, and electronic study of this material demonstrates the emergence of superconductivity in germanium through heavy substitutional doping of Ga metal. This system offers a unique approach towards epitaxial JJs utilizing doped semiconductors that readily interface with their un-doped phase that enables wafer-scale tri-layer qubit fabrication utilizing pristine crystalline materials. I will conclude with a brief discussion on my work at the Massachusetts Institute of Technology further pursuing the development of materials in superconducting quantum computing technology.
[1]: Y. Nakamura, Y. A. Pashkin, and J. S. Tsai, Nature, 398, 786-788 (1999).
[2]: M. P. Bland and F. Bahrami et al., Nature, 647, 343-348 (2025).
[3]: J. A. Steele and P. J. Strohbeen et al., Nat. Nanotechnol., 20, 1757-1763 (2025).

Speaker: Dr Patrick Strohbeen (MIT)

11:30 → 12:00 Research Meeting

Speaker: Joon Sue Lee (University of Tennessee, Knoxville)

12:00 → 14:00 Lunch

Wonhee Ko, Joon Sue Lee, ...

14:00 → 14:30 Research Meeting

Speaker: Ruixing Zhang (Department of Physics and Astronomy, University of Tennessee Knoxville)

14:30 → 15:00 Research Meeting

15:00 → 15:30 Research Meeting

Speaker: Yishu Wang (University of Tennessee Knoxville)

15:30 → 16:00 Research Meeting

Speaker: Hanno Weitering

16:00 → 16:30 Research meeting

Lab tour

Speaker: Wonhee Ko (University of Tennessee, Knoxville)

17:30 → 19:00 Dinner

Wonhee Ko, Ruixing Zhang, Wooin Yang, ...