Superconducting properties of nanocrystalline MgB2
B Lorenz, O Perner, J Eckert, C W Chu
Abstract
Nanocrystalline MgB2 produced by mechanical alloying has been shown to exhibit enhanced superconducting properties such as increased pinning and higher critical currents. However, the effects of the synthesis process on the intrinsic superconducting properties have not been addressed yet. We have investigated the superconducting gap structure of nanocrystalline MgB2 pellets synthesized by high-energy ball milling employing specific heat measurements. We found that the larger σ-gap decreased whereas the smaller π-gap slightly increased in ball milled MgB2 as compared to bulk samples synthesized along the standard routes. The data show that the ball milling process introduces defects that enhance the interband scattering similar to irradiation with neutrons. The reduction of the σ-gap explains the lower superconducting transition temperature of 33 K.
Create a lesson
Related papers
High-Temperature Superconductivity of the Fe-Se-H compound
S. I. Bondarenko, A. A. Prokhorov, N. N. Galtsov et al.
Stabilization of Interband Phase Solitons in Two-Band Noncentrosymmetric Superconducting Rings
Yuriy Yerin, Boris Malomed, Stefan-Ludwig Drechsler et al.
Strain-driven orbital-selective reconstruction and bicollinear-to-stripe evolution in FeTe
Zhenfeng Ouyang, Yin Chen, Yi-Heng Tian et al.
Supercurrent detection and manipulation of topological phase transitions in Shiba-Majorana hybrid systems
Debika Debnath, Ioannis Ioannidis, Paramita Dutta et al.
Exact pair density wave in topological moire flat bands and universal superfluid stiffness
Zhengzhi Wu, Ming-rui Li, Hong Yao
Electrical manipulation of oxygen stoichiometry in multiterminal YBa2Cu3O7-δ junctions
Daniel Stoffels, Caio C. Quaglio-Gomes, Nicolas Lejeune et al.