Impurity- and magnetic-field-induced quasiparticle states in chiral p-wave superconductors
Yao-Wu Guo1, Wei Li2,3(), Yan Chen1,4()
1. Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China 2. State Key Laboratory of Functional Materials for Informatics and Shanghai Center for Superconductivity, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China 3. CAS Center for Excellence in Superconducting Electronics, Shanghai 200050, China 4. Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
Both impurity- and magnetic-field-induced quasiparticle states in chiral p-wave superconductors are investigated theoretically by solving the Bogoliubov–de Gennes equations self-consistently. At the strong scattering limit, we find that a universal state bound to the impurity can be induced for both a single nonmagnetic impurity and a single magnetic impurity. Furthermore, we find that different chiral order parameters and the corresponding supercurrents have uniform distributions around linear impurities. Calculations of the local density of states in the presence of an external magnetic field show that the intensity peak of the zero-energy Majorana mode in the vortex core can be enhanced dramatically by tuning the strength of the external magnetic field or pairing interaction.
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