Fyzikální ústav Akademie věd ČR

Seminář Pondělí, 11.07.2011 14:00 - 15:00

Přednášející: B. Rosenstein (National Chiao Tung University, Hsinchu, Taiwan, R.O.C.)
Místo: Knihovna FZÚ AV ČR, Cukrovarnická 10, Praha 6
Jazyk: anglicky
Pořadatelé: Oddělení magnetik a supravodičů

Core excitations spectrum of the Abrikosov vortex pinned by a dielectric inclusion or nanohole of sizes of order of coherence length is considered using the Bogoliubov - de Gennes equations beyond semiclassical approximation. While the lowest excitation, minigap, in free (or pinned by a metallic defect) vortex is of order Δ²/E_F, it becomes of the order of the superconducting gap Δ (E_F is Fermi energy). The reconstruction of the quasiparticle excitations' spectrum has a significant impact on optical properties and tunneling density of states. We calculate the absorption amplitude and point out that, while in STM the energy gap Δ_DOS is between a quasiparticle state with angular momentum μ^e = μ₀ > 1/2 and quasihole with μ^h = - μ₀, the microwave absorption gap, Δ_dir, is between the states with μ^e = μ_min = μ^h ± 1. It is shown Δ_dir > Δ_DOS.

Přílohy:

rosenstein2011.pdf