To (boldly) measure where no one has measured before: Possibilities for Condensed Matter in Pulsed Magnetic Fields

Boris Maiorov

National High Magnetic Field Laboratory, Los Alamos National Laboratory

Friday, November 8, 2024

2:00pm

NW17-218 Hybrid

PSFC Seminars

                                                                                   

Abstract: Magnetic field is one of the principal variables we can change to study condensed matter. The generation of strong magnetic fields is also key for a large number of applications such as MRIs, Maglebs, rails gun, material growth, and isotope separation.

However, accessing repeatedly and non-destructively magnetics fields above 40T requires pulsed magnetic fields, which bring problem with fast changing magnetic fields, high-vibration environment, large electrical noise and short amount of time for measurements. These conditions require developing unique techniques to solve such exceptional challenges. In this talk I will show several examples of techniques and systems where pulsed fields can access.

In particular, the promise of fusion technology enabled by high magnetic fields produced by high temperature superconductors flexible tapes and recent records in all-superconducting magnets reinforce the need to study critical current density (J_c) in magnetic fields above 30T. Achieving J_c measurements in pulsed magnetic fields provides a tool for this. Using Fast Programmable Gate Array electronics, we measured reproducible current–voltage curves (I-V) in different superconductor thin films on single crystals and metal substrates grown by different methods. We show it is possible to measure J_c in high pinning coated conductors up to 65T. We compare measurements in two of the magnet systems available at Los Alamos Pulsed Field Facility of the National High Magnetic Field Laboratory and show that we are now able to measure J_c continuously as a function of field (H) in our newly commissioned mid-pulse magnet. We explore extending J_c determination to higher dH/dt and compare the J_c performance of standard samples and those with nanoparticle additions, and irradiated samples that are key to predict the performance and lifespan of compact fusion reactors.  

Bio: Dr. Boris Maiorov is a scientist at Los Alamos National Laboratory (LANL), with a focus on physics, superconductivity, and elastic constants. His academic journey started in Argentina where he completed his Undergraduate and Doctoral degrees in Physics at the Instituto Balseiro, Bariloche. He has contributed significantly to the field of superconductivity, particularly in enhancing critical current densities and optimizing pinning landscapes, with unique work on very high fields. Boris explores the relation between material defects and superconducting vortices as models of strongly interacting systems aimed on improving the pinning properties. His studies the synergetic combination of different types of material defects to improve superconductor performance, and his research on angular-dependent vortex pinning mechanisms has been widely recognized as a tool to identify relevant material defect to improve superconductor’s performance. His recent efforts are focused on finding alternative ways to improve superconductors using thermodynamic routes. He leads the efforts of ultrasound studies and non-linear electrical transport in the National High Magnetic Field Laboratory (Pulsed Field Facility at LANL) where he uses and develops unique techniques to take advantage of the highest non-destructive magnetic fields in the world available there.

He is a Senior Member of IEEE and member of the Board of the Applied Superconductivity Educational Foundation. In his free time, he plays different brass instruments in the Los Alamos Community Winds Band and Santa Fe Community Orchestra.