Superconductivity in Dense $MgB_2$ Wires

P. C. Canfield; D. K. Finnemore; S. L. Bud'ko; J. E. Ostenson; G. Lapertot; C. E. Cunningham; C. Petrovic

doi:10.1103/PhysRevLett.86.2423

paper

Superconductivity in Dense $M g B_{2}$ Wires

arXiv:cond-mat/0102289 · doi:10.1103/PhysRevLett.86.2423

Abstract

$M g B_{2}$ becomes superconducting just below 40 K. Whereas porous polycrystalline samples of $M g B_{2}$ can be synthesized from boron powders, in this letter we demonstrate that dense wires of $M g B_{2}$ can be prepared by exposing boron filaments to $M g$ vapor. The resulting wires have a diameter of 160 $μ m$ , are better than 80% dense and manifest the full $χ = - 1/4 π$ shielding in the superconducting state. Temperature-dependent resistivity measurements indicate that $M g B_{2}$ is a highly conducting metal in the normal state with $ρ (40 K)$ = 0.38 $μ O hm$ - $c m$ . Using this value, an electronic mean free path, $l \approx 600 A ˚$ can be estimated, indicating that $M g B_{2}$ wires are well within the clean limit. $T_{c}$ , $H_{c 2} (T)$ , and $J_{c}$ data indicate that $M g B_{2}$ manifests comparable or better superconducting properties in dense wire form than it manifests as a sintered pellet.

Figures' layout fixed

Superconductivity in Dense $M g B_{2}$ Wires

Abstract

References in corpus (2)

Cited by in corpus (123)

Superconductivity in Dense MgB2​ Wires

Abstract

References in corpus (2)

Cited by in corpus (123)

Superconductivity in Dense $M g B_{2}$ Wires