72 research outputs found
Relation between Vortex Excitation and Thermal Conductivity in Superconductors
Thermal conductivity under a field is investigated in
-wave superconductors and isotropic s-wave superconductors by the
linear response theory, using a microscopic wave function of the vortex lattice
states. To study the origin of the different field dependence of
between higher and lower temperature regions, we analyze the
spatially-resolved thermal conductivity around a vortex at each temperature,
which is related to the spectrum of the local density of states. We also
discuss the electric conductivity in the same formulation for a comparison.Comment: 9 pages, 11 figures, to appear in European Physical Journal
Site-selective NMR for odd-frequency Cooper pairs around vortex in chiral p-wave superconductors
In order to identify the pairing symmetry with chirality, we study
site-selective NMR in chiral p-wave superconductors. We calculate local nuclear
relaxation rate 1/T_1 in the vortex lattice state by Eilenberger theory,
including the applied magnetic field dependence. We find that 1/T_1 in the NMR
resonance line shape is different between two chiral states
p_{pm}(=p_x{pm}ip_y), depending on whether the chirality is parallel or
anti-parallel to the vorticity. Anomalous suppression of 1/T_1 occurs around
the vortex core in the chiral p_- wave due to the negative coherence term
coming from the odd-frequency s-wave Cooper pair induced around the vortex with
Majorana state.Comment: 6 pages, 4 figure
Magnetization process in a chiral p-wave superconductor with multi-domains
A simulation study for the magnetization process is performed for the
multi-domain state in a chiral p-wave superconductor, using the time-dependent
Ginzburg-Landau theory. The external field penetrates inside as core-less
vortices through the domain wall, forming the vortex sheet structure. We find
that, with increasing magnetic fields, the domain walls move so that the
unstable domains shrink to vanish. Therefore, the single domain structure is
realized at higher fields
Flux flow and pinning of the vortex sheet structure in a two-component superconductor
A simulation study using the time-dependent Ginzburg-Landau theory is
performed for the vortex state in two-component superconductors, such as
PrOs_4_Sb_12_. We investigate the flux flow and the pinning of the vortex sheet
structure. We find domain wall that traps half flux-quantum vortices and moves
with the flux flow. In the pinning case, we observe an emitting process of a
conventional vortex from the vortex sheet by combining a pair of half
flux-quantum vortices.Comment: 4 pages, 4 figures, to appear in Phys. Rev.
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