2001/03/20 by Chang‐Beom Eom, C. B. Eom, M. K. Lee +36 · 4 citations
Materials Science · Physics and Astronomy · #Atomic physics #Condensed matter physics #Critical current #Critical field #Field (mathematics) #Helium #Iron-based superconductors research #Liquid helium #Magnetic field #Materials science #Nanotechnology #Physics #Physics of Superconductivity and Magnetism #Superconductivity #Superconductivity in MgB2 and Alloys #Thin film #Transition temperature #cond-mat.supr-con
paper · pdf · doi:10.1038/35079018
published as Nature 411 (2001) 558-560 · 4 pages pdf, submitted to Nature 3/20/01
arxiv created 2001/03/20 · openalex publication_date 2001/05/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The discovery of superconductivity at 39 K in magnesium diboride offers the possibility of a new class of low-cost, high-performance superconducting materials for magnets and electronic applications. With twice the critical temperature of Nb3Sn and four times that of Nb-Ti alloy, MgB2 has the potential to reach much higher fields and current densities than either of these technological superconductors. A vital prerequisite, strongly linked current flow, has already been demonstrated even at this early stage. One possible drawback is the observation that the field at which superconductivity is destroyed is modest. Further, the field which limits the range of practical applications, the irreversibility field H*(T), is ~7 T at liquid helium temperature (4.2 K), significantly lower than ~10 T for Nb-Ti and ~20 T for Nb3Sn. Here we show that MgB2 thin films can exhibit a much steeper temperature dependence of H*(T) than is observed in bulk materials, yielding H*(4.2 K) above 14 T. In addition, very high critical current densities at 4.2 K, 1 MA/cm2 at 1 T and 105 A/cm2 at 10 T, are possible. These data demonstrate that MgB2 has credible potential for high-field superconducting applications.