Quasiparticle excitation in and around the vortex core of underdoped YBa2Cu4O8 studied by site-selective NMR

Article

关键词: SPIN-LATTICE RELAXATION;    QUASI-PARTICLE SPECTRA;    DENSITY-OF-STATES;    T-J MODEL;    D-WAVE;    MIXED-STATE;    ELECTRONIC-STRUCTURE;    FIELD DEPENDENCE;    SUPERCONDUCTORS;    YBA2CU3O7-DELTA;   

DOI  :  10.1103/PhysRevB.65.060503

来源: SCIE

【 摘 要 】

We report a site-selective O-17 spin-lattice relaxation rate T-1(-1) in the vortex state of underdoped YBa2Cu4O8, We found that T-1(-1) at the planar sites exhibits an unusual nonmonotonic NMR frequency dependence. In the region well outside the vortex core, T-1(-1) cannot be simply explained by the density of states of the Doppler-shifted quasiparticles in the d-wave superconductor. Based on T-1(-1) in the vortex core region, we establish strong evidence that the local density of states within the vortex core is strongly reduced.

【 授权许可】

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