Maxime Leroux1 Fedor Balakirev1 Masashi Miura2 Boris Maiorov1

1, Los Alamos National Laboratory, Los Alamos, New Mexico, United States
2, Seikei University, Tokyo, , Japan

With the advent of all-superconducting very-high field (>20T) magnets, it becomes technologically relevant to study superconducting critical currents in magnetic fields in the range of 20 to 65 T. New challenges to vortex pinning understanding may also emerge at such very-high fields and low temperatures. For example, are thermal fluctuations as important at high-fields/low-temperatures as they are at liquid Nitrogen temperatures near the irreversibility line?
We present critical current measurements obtained by electrical transport measurements in pulsed magnetic fields up to 65T. The use of Fast Programmable Gate Array (FPGA) facilitates fast measurements/decision times permitting multiple current-voltage (I-V) curves measurements in a single magnetic field pulse lasting 50ms.
We study and compare standard YGdBa2Cu3O7 coated conductors with and without BaHfO3 nanoparticles grown by Metal Organic Deposition. These films have shown great results in terms of critical current enhancement up to 9T at high and low temperatures owing to the small size of BaHfO3 nanoparticles. Our results show continuous improvement for samples with BaHfO3 and will be analyzed in detail in the presentation.