Effect of a magnetic field on the quasiparticle recombination in superconductors

Article

关键词: PAIR-BREAKING;    TIME;    QUASIPARTICLE;    LIFETIMES;    FILMS;    DYNAMICS;    ALLOYS;   

DOI  :  10.1103/PhysRevB.87.140502

来源: SCIE

【 摘 要 】

Quasiparticle recombination in a superconductor with an s-wave gap is typically dominated by a phonon bottleneck effect. We have studied how a magnetic field changes this recombination process in metallic thin-film superconductors, finding that the quasiparticle recombination process is significantly slowed as the field increases. The magnetic field disrupts the time-reversal symmetry of the pairs, giving them a finite lifetime and decreasing the energy gap. The field could also polarize the quasiparticle spins, producing different populations of spin-up and spin-down quasiparticles. Both processes favor slower recombination; in our materials we conclude that strong spin-orbit scattering reduces the spin polarization, leaving the field-induced gap reduction as the dominant effect and accounting quantitatively for the observed recombination rate reduction. DOI: 10.1103/PhysRevB.87.140502

【 授权许可】

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