Chiral Majorana fermion modes regulated by a scanning tunneling microscope tip

Yan-Feng Zhou, Zhe Hou, Ying-Tao Zhang, Qing-Feng Sun
2018 Physical review B  
The Majorana fermion can be described by a real wave function with only two phases (0 and {\pi}) which provide a controllable degree of freedom. We propose a strategy to regulate the phase of the chiral Majorana state by coupling with a scanning tunneling microscope tip in a system consisting of quantum anomalous Hall insulator coupled with a superconductor. With the change of the chemical potential, the chiral Majorana state can be tuned alternately between 0 and {\pi}, in which,
more » ... hich, correspondingly, the perfect normal tunneling and perfect crossed Andreev reflection appear. The perfect crossed Andreev reflection, by which a Cooper pair can be split into two electrons going into different terminals completely, leads to a pumping current and distinct quantized resistances. These findings may provide a signature of Majorana fermions and pave a feasible avenue to regulate the phase of Majorana state.
doi:10.1103/physrevb.97.115452 fatcat:mve24rissbbavfgkp3l2n7eadi