Berkeley Lab

Tengming Shen Wins Cryogenic Society’s Boom Award

From ATAP News, November 2020

Tengming ShenTengming Shen, a staff physicist in ATAP’s Superconducting Magnet Program, is being given the Roger W. Boom Award by the Cryogenic Society of America. The award will be presented on November 4th at the virtual 2020 Applied Superconductivity Conference.

The award cites “his outstanding research on high-temperature superconducting materials and magnets  and especially his contributions to  understanding the Bi-2212 round wire technology, improving its critical current density by intelligent processing, and demonstrating its excellent properties in prototype accelerator magnets.” It also recognizes Tengming’s activity in “educating and mentoring young research engineers, including underrepresented groups, within a U.S. Department of Energy national lab setting.”

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He and his team are working to transform high-Tc superconducting materials into practical magnet conductors in order to build a spectrum of powerful superconducting magnets impossible with low-Tc superconductors such as niobium-titanium (Nb-Ti) and niobium-three-tin (Nb3Sn). One goal is to use these new materials to build a high-field accelerator dipole that is 2.5 times more powerful than the 8.3 T Nb-Ti LHC main dipole, by taking advantage of their excellent ability to carry high current amid high magnetic fields (up to 100 T at 4.2 kelvins).

The work, if successful, will likely also open new avenues to building magnets similar in power to Nb-Ti and Nb3Sn magnets but operating at 20-77 K.  These would be potentially cheaper to operate than Nb-Ti and Nb3Sn magnets, which typically work at the liquid-helium temperatures of 1.8 or 4.2 K.

Bismuth-2212 is among the high-temperature superconductors being investigated by the program. Shen and his team are working to transform high-Tc superconducting material into practical magnet conductors in order to build a spectrum of powerful superconducting magnets impossible with traditional superconductors such as niobium-titanium (NbTi) and niobium-three-tin (Nb3Sn).

One goal is to use these new materials to build a high-field accelerator dipole that is 2.5 times more powerful than the 8.3 T Nb-Ti LHC main dipole, by taking advantage of their excellent ability to carry high current amid high magnetic fields (up to 100 T at 4.2 kelvins). The work, if successful, will likely also open new avenues to building magnets similar in power to NbTi and Nb3Sn magnets but operating at 20-50 K, potentially much cheaper to operate than NbTi and Nb3Sn magnets, which typically work at the liquid-helium temperatures of 1.8 or 4.2 K.

To effectively generate magnetic fields, practical superconductors need to carry a high engineering current density, Je, of 600 A/mm2 over long lengths. (Je=Ic/A: the critical current of the superconductor divided by the cross section of the composite superconducting wire.)  Tengming and his collaborators have succeeded in understanding microstructures and mechanisms that control Ic in superconducting wires of Bi-2212 (the only multifilamentary high-temperature superconducting cuprate round wire). Leveraging an industry, university, and national lab collaboration under the framework of ATAP-headquartered US Magnet Development Program, the team recently improved the Je of Bi-2212 industrial wires to 1000 A/mm2 at 4.2 K and 27 T and demonstrated that high Je and excellent quench properties are possible with coils fabricated from high-current Bi-2212 Rutherford cables. They are building prototype accelerator magnets using a canted-cosine-theta design developed by Shlomo Caspi and colleagues in ATAP’s Superconducting Magnet Program.

His several other current endeavors include collaborations with Fermilab and Composite Technology Development, Inc., in Colorado a to develop advanced resin and insulation technologies for Nb3Sn accelerator magnets; with Berkeley Lab’s National Center for Electron Microscopy and the University of California, Berkeley to develop 1-kelvin Nb-Ti superconducting electron microscopes; with Brookhaven National Lab,  KEK and Kyoto University to develop HTS magnets for a high radiation environment; and with an ATAP team led by Lucas Brouwer to develop achromatic, cryogen-free high-Tc magnets for proton therapy gantries.

Tengming is a former Peoples Fellow at Fermilab and recipient of a prestigious Early Career Research Program award from the U.S. Department of Energy, Office of High Energy Physics. He received his Ph.D. in electrical engineering from the Florida State University in 2010 with a thesis work at the National High Magnetic Field Laboratory.

The Roger W. Boom Award is named in honor of the late emeritus professor from the University of Wisconsin. Dr. Boom’s career spanned more than thirty years, during which he motivated a great number of young scientists and engineers to pursue careers in cryogenic engineering and applied superconductivity. This award was created by the CSA to be given to a young professional (under 40 years of age) who “shows promise for making significant contributions to the fields of cryogenic engineering and applied superconductivity. The spirit of the Boom Award is to recognize young people for their pursuit of excellence, demonstration of high standards and clear communications.