A very active research area in superconductivity is the performance improvementofthe current carrying capability (Jc). Here, we show that the depairing current (Jd) can beincreased by controlling the penetration depth (λ) and coherence length (ξ) in the two most representative materials: in REBa2Cu3Oy we increased the carrier density to decrease λ and ξ, and in BaFe2(As1-xPx)2 we tuned the chemical pressure. The combination ofthese thermodynamic and flux-pinning optimization routes leads to a dramatic increase of Jc to Jc ~150 MA/cm2 at 4.2 K (32.4% of Jd) for REBa2Cu3Oy, the highest value ever reported for any superconductor.
- Masashi Miura
- Go Tsuchiya
- Boris Maiorov