High current density and superconducting critical current (Jc) measurements in pulsed magnetic fields are made possible with the combination of sample shaping via Focused Ion Beam (FIB) and fast measurement logic realized in Field Programmable Gate Array (FPGA) instrumentation.
FIB lithography allows reducing sample cross-section as well as making electrical contacts on sub-micron scale, making possible current densities as high as MA cm2. FPGA logic can track and respond to changes in sample properties (e.g. onset of dissipation) within microseconds, protecting the sample and recording the signal.
P.J.W. Moll, et al, High magnetic-field scales and critical currents in SmFeAs(O,F) crystals, Nat. Mater. 9 (2009) Read online.
S.A. Baily, et al, Pseudoisotropic Upper Critical Field in Cobalt-Doped SrFe2As2, Phys. Rev. Lett. 102 (2009) Read online.
F.F. Balakirev, et al, Quantum phase transition in the magnetic-field-induced normal state of optimun-doped high-TC cuperate superconductors at low temperatures, Phys. Rev. Lett. 102 (2009) Read online.
Last modified on 27 December 2022