title: Upward shift of the vortex solid phase in high-temperature-superconducting wires through high density nanoparticle addition.
abstract: We show a simple and effective way to improve the vortex irreversibility line up to very high magnetic fields (60T) by increasing the density of second phase BaZrO3 nanoparticles. (Y0.77,Gd0.23)Ba2Cu3Oy films were grown on metal substrates with different concentration of BaZrO3 nanoparticles by the metal organic deposition method. We find that upon increase of the BaZrO3 concentration, the nanoparticle size remains constant but the twin-boundary density increases. Up to the highest nanoparticle concentration (n ~ 1.3 × 10(22)/m(3)), the irreversibility field (Hirr) continues to increase with no sign of saturation up to 60 T, although the vortices vastly outnumber pinning centers. We find extremely high Hirr, namely Hirr = 30 T (H||45°) and 24 T (H||c) at 65 K and 58 T (H||45°) and 45 T (H||c) at 50K. The difference in pinning landscape shifts the vortex solid-liquid transition upwards, increasing the vortex region useful for power applications, while keeping the upper critical field, critical temperature and electronic mass anisotropy unchanged.
authors: Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.|Graduate School of Science &Technology, Seikei University, 3-3-1 Kichijoji-kitamachi, Musashino-shi, Tokyo 180-8633, Japan.
authors: Masashi
authors: M
authors: Miura
authors: Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Boris
authors: B
authors: Maiorov
authors: Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Fedor F
authors: FF
authors: Balakirev
authors: Materials R&D Laboratory, Japan Fine Ceramics Center, 2-4-1 Mutsuno, Atuta-ku, Nagoya 456-8587, Japan.
authors: Takeharu
authors: T
authors: Kato
authors: Graduate School of Science &Technology, Seikei University, 3-3-1 Kichijoji-kitamachi, Musashino-shi, Tokyo 180-8633, Japan.
authors: Michio
authors: M
authors: Sato
authors: Superconductivity Research Laboratory, International Superconductivity Technology Center, KSP R&D Wing A-9F, 3-2-1 Sakado, Takatsu-ku, Kaswasaki-shi, Kanagawa, 213-0012 Japan.
authors: Yuji
authors: Y
authors: Takagi
authors: Superconductivity Research Laboratory, International Superconductivity Technology Center, KSP R&D Wing A-9F, 3-2-1 Sakado, Takatsu-ku, Kaswasaki-shi, Kanagawa, 213-0012 Japan.
authors: Teruo
authors: T
authors: Izumi
authors: Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: Leonardo
authors: L
authors: Civale