The Cryogenic Society of America is very proud of the recipients of our Roger W. Boom Award, which is given to young persons showing promise for important contributions to cryogenic engineering and applied superconductivity. Over the years since 1996, when the first Boom award was made to Dr. Christopher Rey, we have watched as our awardees have moved ahead in their fields, living up to the promise the Boom awards committee saw in them. For this issue, we caught up with several Boom awardees and asked them to update us on the specifics of their career advances.

Prof. Jeffrey Parrell

Since the time of the Boom Award in 2006, Dr. Parrell continued to develop Nb3Sn, Nb-Ti and HTS conductors for a variety of applications. In his present role as VP/general manager at Oxford Superconducting Technology (OST) in Carteret NJ, he has worked with his OST colleagues to develop and successfully produce internal tin Nb₃Sn for the ITER toroidal field magnets. They are also currently working to complete R&D for Nb₃Sn strands for planned upgrades to the LHC at CERN.

Prof. Justin Schwartz

Since winning the Boom Award in 1998, Professor Schwartz has remained active in research related to high temperature superconducting magnets and materials. In 2003, his group, in collaboration with Oxford Superconducting Technology, was the first to generate a magnetic field of 25 T using an HTS insert, a result that helped lead to worldwide interest in high field superconducting magnets. In 2004, Schwartz was named a Fellow of the Institute of Electrical and Electronics Engineers (IEEE) “for contributions to high temperature superconductors and magnet systems,” and in 2015 he was named a Fellow of the American Association for the Advancement of Science “for distinguished contributions to the field of applied superconductivity, particularly for the advancement of high magnetic fields and for the integration of experiment and computation.” In 2004 he also served as the chair of the Applied Superconductivity Conference, and from 2005-2012 Schwartz served as the editor-in-chief of the IEEE Transactions on Applied Superconductivity. He and his collaborators were also the recipients of the 2012 and 2013 Van Duzer Prizes, awarded by the IEEE Council on Applied Superconductivity for best paper in the IEEE Transactions on Applied Superconductivity. Schwartz remained at Florida State University until 2009, at which time he moved to North Carolina State University to become the Kobe Steel Distinguished Professor and head of the Department of Materials Science and Engineering, positions he continues to hold today.

Dr. Chao Wang

In the past few years, Dr. Wang has been focusing on the development of liquid helium solutions to combat the worldwide helium shortage. He has developed and commercialized small-scale helium liquefiers based on the 4K pulse tube cryocoolers for the first time in the world. These liquefiers can liquefy helium at rates from 15 to 60 liters per day. Hundreds of laboratories all over the world have benefited from these small helium liquefiers that can recycle more than 99 percent of the helium and reliquefy, enabling the laboratories to produce their own liquid helium supply.

Wang also developed and commercialized helium reliquefiers by using 4K pulse tube cryocoolers. These reliquefiers can be installed into existing liquid helium cryostats to build a closed helium cycle. Many applications around the world, such as wet PPMS, MPMS, dilution refrigerators and superconducting magnets, have been installed with these reliquefiers, without needing to be refilled with liquid helium.

Wang has recently made a few more innovations on cryogenic refrigeration. He invented a 1K closed cycle system with extremely low vibration and an extra low vibration 4K cryostat. These systems have been used in some applications to replace liquid helium. New cold helium circulation systems have been developed by his team to provide remote cooling with very low vibration.

Dr. Gregory Nellis

Dr. Nellis received the Boom Award in 2008. Since that time he has worked on writing two textbooks, Heat Transfer and Thermodynamics, with his co-author Sanford Klein. These textbooks are the first to tightly integrate the subject matter with computer tools and therefore allow students to tackle much more interesting, real-world engineering problems than are typically possible in undergraduate classes. He is currently working on the second edition of the book Cryogenic Heat Transfer with Professor Randall Barron. Nellis’ research continues to be primarily in the area of cryogenic refrigeration cycles, with recent projects focusing on magnetic refrigeration, pulse-tube regenerators and mixed-gas Joule-Thomson (MGJT) cycles. Over the last several years, two test facilities have been constructed in the Cryogenic Lab at the University of Wisconsin that are dedicated to MGJT research. The first is a two-stage MGJT system that is fully instrumented and flexible, allowing the cycle to be run with various working fluids and over a range of operating conditions. The second is a heat transfer test facility capable of precisely measuring the multi-phase, multi-component heat transfer coefficient over a range of cryogenic conditions.

Dr. Joel Ullom

Dr. Ullom leads the Quantum Sensors Project at the NIST Boulder Laboratories. His group’s research spans a number of areas related to superconducting sensors and milli­Kelvin cryogenics. One current project is the detection of ultrafast structural dynamics using a laser-driven X-ray plasma source and a high resolution X-ray spectrometer built from an array of transition-edge microcalorimeters. Another project is the construction of an adiabatic demagnetization refrigerator (ADR) precooled by a two-stage pulse tube and a Helium-3 sorption cooler. The Helium-3 unit provides a
300 mK heat intercept that allows the connection of multiple coaxial cables to the cold stage of the ADR. This refrigerator architecture will be useful for the development and dissemination of cryogenic sensor arrays read out using microwave techniques. A final project is the development of large arrays of superconducting millimeter-wave polarimeters for studies of the cosmic microwave background.

Dr. Terry Grimm

Since receiving the Boom Award in 2004, Dr. Grimm was a key contributor to the design team for the Facility for Rare Isotope Beams, now under construction at Michigan State University. In 2005 Grimm founded Niowave, Inc., to develop commercial applications of superconducting electron linacs. As president and senior scientist, Grimm leads Niowave in its efforts to focus on four primary commercial markets: medical isotope production, high power X-ray machines, free electron lasers and high intensity neutron sources. Niowave has experienced dramatic growth since 2005 and has expanded twice, nearly doubling its testing and production facilities.

In 2010 Niowave became the first private laboratory in the world to demonstrate a photoelectron beam from a superconducting accelerator, and in 2012 became the first laboratory in the world to accelerate a beam with a superconducting spoke structure. Niowave has been the recipient of numerous local, state and national awards, including being named a 2010 Department of Energy Small Business of the Year and receiving the 2010 IEEE Award for Entrepreneurship in the field of Applied Superconductivity.