演講 『Dr. Kimitoshi Kono：An evidence for Majorana fermions on the surface of superfluid 3He-B phase』
Superfluid 3He is a BCS type p-wave superfluid. Ions moving in the superfluid 3He scatter off thermally excited quasiparticles and the transport properties are determined by the quasiparticle scattering. The 3He-A phase is characterized by the psuedovector field of Cooper pair orbital-angular-momentum, which aligns perpendicularly to the surface. This chiral symmetry breaking results in a skew scattering of quasiparticles from the moving ions. And hence, the anomalous Hall effect (AHE) of ion current occurs. Our observation of this AHE is quantitatively explained by the recent theory.
In the vicinity of the surface of the 3He-B phase, on the other hand, low-energy quasiparticle subgap surface bound states form, which have been known as the Andreev surface bound states (ASBS). Chung and Zhang unvailed that the ASBS are Majorana fermions. We observed an
excess scattering from the ASBS in the surface ion mobility. Surprisingly, it does show no depth dependence, however. The recent theory of Tsutsumi showed that the observed properties of ion mobility accord with the concept of Majorana fermions. We now obtain a clear evidence for the surface Majorana fermions in the superfluid 3He-B phase.
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