Carbohydrate doping to enhance electromagnetic properties of MgB2 superconductors

The effect of carbohydrate doping on lattice parameters, microstructure, T-c, J(c), H-irr, and H-c2 of MgB2 has been studied. In this work the authors used malic acid as an example of carbohydrates as an additive to MgB2. The advantages of carbohydrate doping include homogeneous mixing of precursor powders, avoidance of expansive nanoadditives, production of highly reactive C, and significant enhancement in J(c), H-irr, and H-c2 of MgB2, compared to undoped samples. The J(c) for MgB2+30 wt % C4H6O5 sample was increased by a factor of 21 at 5 K and 8 T without degradation of self-field J(c). (c) 2006 American Institute of Physics.